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Dr Jack Kruse joins me in an epic three-hour interview to weave the story of human evolution fundamentally tied to light. He describes our transition from furry ground dwelling mammals to upright walking primates, the critical role of the POMC gene, melanin and function of mitochondria as producers of endogenous light, as well as the distortion of the light environment as the key underlying driver of modern chronic disease.Dr Jack Kruse is a neurosurgeon, biophysicist, health optimisation researcher and founding father of the circadian health / mitochondrial medicine movement. This is the first in a series of interviews with Dr Kruse that will also cover water and magnetism, two further installments in a trilogy that strongly challenges the centrality of diet as the chief determinant of optimal health. Stay tuned for further episodes. *This is not a podcast for beginners, and if you want the cliff notes I'd suggest watching Dr Max's summary takes and the closing thoughts. Some explicit language in this interview – Dr Jack is extremely passionate!TIMESTAMPS00:00:00 Dr Max's intro00:05:11 Dr Kruse's backstory00:10:22 Differences between centralized and decentralized medicine00:12:32 Incongruence in Darwin's theories of evolution00:13:27 Evolution of mammals from ground dwelling creatures00:17:57 The POMC gene and its cleavage products allowed mammals to survive the dinosaur extinction event00:28:12 POMC, the leptin melanocortin pathway and human metabolism00:34:37 POMC and autoimmunity00:38:42 To understand the effect of light on biology, we need to understand physics00:41:15 UV light from the sun is critical to stimulating POMC00:46:42 Robert O. Becker's research on bioelectrics and cellular DC electric current00:50:22 POMC, melanin and biological semi-conductors00:59:52 Dr Max's summary of the first hour01:05:05 What is leptin and its function?01:12:28 All mammalian cells generate UV light in the mitochondria and use it to signal01:19:27 The biological function of melanin01:26:19 Dr Max's summary of the function of leptin01:30:05 Reversing vitiligo, grey hair & melanin loss with sun & UV light01:36:43 Melanoma develops in absence of full spectrum (red/infrared) sunlight01:39:38 Dr Max's summary of the first 1.5 hours01:41:22 What are mitochondria?01:47:29 Competing theories on the factors that influenced development of human brain01:49:27 History of biological semi-conductors and importance of DHA in the SN2 position01:56:36 Photoreceptors, neuropsin and mental health conditions 02:08:00 Incongruent light signals between eye and skin creates disease02:12:47 The harms of taking exogenous melatonin02:17:52 Why blocking UV light causes melanoma02:24:32 Rebuttals to ‘light causes all diseases' point of view02:38:42 Understanding light is critical to understanding the root causes of patients diseases02:54:03 Dr Kruse's take on premature male pattern balding and refractory error aka ‘soyjak meme'02:59:49 Why we see low serum Vitamin D in overweight or obese people03:04:49 Dr Jack's closing thoughts03:08:02 Three actionable steps for the listener FURTHER READINGSee Youtube show notes for full list - unable to fit here
Sn2 E6“ Romancing?!” This episode, MsCC response to an Instagram mention from fellow podcasters concerning women and romance. She also shares updates regarding guests plus so much more, it's a short episode but straight facts. Shoutout to our sponsor Fôrwərd Ever, visit Frwdever.com Free SH with code TMMPODCAST. Thank you for tapping in. We hope you enjoy our content. Your comments are welcome. Email us ttmmpodcast@gmail.com
In this video we'll be helping you decide which way a reaction will go with certain conditions (SN1, SN2, E1, and E2) Timestamp: (0:49) - Nucleophilicity and Basicity (rows) (1:13) - Nucleophilicity and Columns (2:00) - Reagent acting as nucleophile only (2:25) - Reagent acting as a strong base only (2:44) -Reagent acting as strong base / strong nucleophile (3:20) -Reagent acting as weak base/ weak nucleophile (3:47) -Reagent acting as nucleophile only (primary or secondary substrate) (4:09) -Reagent acting as nucleophile only (tertiary substrate) (4:20) -Reagent acting as a strong base only (primary, secondary, or tertiary substrate) (4:39) -Reagent acting as strong base / strong nucleophile (primary substrate) (5:04) -Reagent acting as strong base / strong nucleophile (secondary substrate) (5:13) -Reagent acting as strong base / strong nucleophile (tertiary substrate) (5:28) -Reagent acting as weak base/ weak nucleophile (primary or secondary substrate) (5:36) -Reagent acting as weak base/ weak nucleophile (tertiary substrate) (6:00) -Regiochemistry/Stereochemistry for SN1 (6:13) -Regiochemistry/Stereochemistry for SN2 (6:22) -Regiochemistry/Stereochemistry for E1 (6:29) -Regiochemistry/Stereochemistry for E2
In this video we'll be comparing all the reactions (SN1, SN2, E1, and E2). Timestamp: (0:00) - Intro (0:33) - Rate Law differences (1:12) - Base/Nucleophile differences (2:33) - Substrate differences (4:07) -Solvent differences (4:53) -Stereochemistry differences (6:02) -Rearrangement differences
In this video we'll be comparing E1 and E2 Reactions Timestamp: (0:00) - Intro (0:31) - E1 Rate Law (0:49) - E2 Rate Law (0:58) - E1 two step reaction (1:20) - E2 concerted reaction (1:33) - E1 (base) (1:54) - E2 (base) (2:11) - E1 (substrate) (2:34) - E2 (Substrate) (2:46) - E1 (leaving group) (2:59) - E2 (leaving group) (3:12) - E1 (stereochemistry) (3:31) - E2 (stereochemistry) (3:57) - E1 (rearrangement) (4:12) -E2 (rearrangement)
In this video, we'll be comparing SN1 and SN2 reactions. (0:00) Intro (0:49) -Definition (Nucleophile, Electrophile, Leaving Group, Substrate) (1:13)- SN1 Rate Law 1:28- SN2 Rate Law (1:36)- SN1 two-part reaction (1:55) -SN2 concerted reaction (2:20) -SN1 nucleophile (2:43)- SN2 nucleophile (3:18)- SN1 substrate (3:51)- SN2 substrate (4:21)- SN1 solvent (4:34)- SN2 solvent (4:47)- SN1/SN2 leaving group (5:40)- SN1 stereochemistry (6:04)- SN2 stereochemistry (6:22)- SN1 rearrangement (6:43)- SN2 rearrangement Check out the visual aspect here on our YouTube: https://youtu.be/4XlJZokd5Dc Music from Tunetank.com danyvin - Pretty Lofi (Copyright Free Music) Download free: https://tunetank.com/t/1ugo/3741-pretty-lofi
In this episode, we'll be going over SN2 reactions and the factors affecting it. (0:00)- Intro (0:22)- Definitions (Nucleophile, Electrophile, Leaving Group, Substrate) (0:40)- General SN2 reaction (2:24)- SN2 Reaction- The Great Rear Ended Car Crash (3:06)- SN2 and strength of nucleophile (3:58)- Steric effects of electrophile (4:55)- Solvents 6:03- Leaving Group (7:14)- Stereochemistry (8:24)- SN2 Summary Sheet Check out the visual aspect of this video on our youtube. https://youtu.be/tOgInZX4Xgo
Ep.3-Sn2. Holiday Kinks & Cookies: Sexy Seasonal Ideas Sam Silver, @x_alamode is back to help us share some Holiday treats to get your ready for 2020! Our Fitness curator and Host @oraclejd will be sharing her “PLEASURABLE
This course give you the Complete discussion of on nucleophilic Substitution reaction of Alkyl halide where you will get everything related to understanding of this chapter including terms such as nucleophile, base, leaving group, its nature, strength, concepts, mechanism and stereochemistry of reactions, comparison of SN1, SN2, E1, E2 with details of it. What you'll learn This course is giving you complete understanding of the chapter "Nucleophilic Substitution and elimination reactions of alkyl halide from the book of Solomons, Fryhle & Snyder Introduction of Alkyl halide Concept of Nucleophilic Substitution Reaction Concept of Nucleophile Concept of Leaving Groups Kinetics of a nucleophilic substitution reaction SN2 Mechanism of SN2 Reaction Concept of SN1 Reaction Mechanism of SN1 Reaction Carbocation Stereochemistry of SN1 Reaction Factors affecting rates of SN1 and SN2 Reaction Summery of SN1 Ans SN2 Reaction Organic synthesis and functional group transformation Elimination Reaction of alkyl halide Concept of E2 Reaction Concept of E1 Reaction How to determine whether substitution or elimination reaction to take place Overall Summary Are there any course requirements or prerequisites? This course give complete information of the topic so there is no prerequiresites. here I will discuss starting from ground level. Who this course is for: Current organic chemistry students, or students about to start organic chemistry who are looking to get ahead Homeschool parents looking for extra support with organic chemistry Chemists Chemical engineers Professionals working in chemical, petrochemicals, pharmaceuticals, cosmetics, oil and gas industries Anyone who seeks to broaden the sphere of his knowledge and discover the fascinating world of organic chemistry Anyone who wants to study organic chemistry for fun after being away from university for a while IIT JEE Aspirants NEET Aspirants
Join the fan chat on Discord! Link: https://discord.gg/FupzWf Musk's Top Concern Now Is SpaceX Getting to Mars Before He Dies Link: https://www.bloomberg.com/news/articles/2020-03-09/elon-musk-worries-spacex-won-t-get-to-mars-before-he-dies While others worry about economies slipping into recession and markets melting down, Elon Musk's biggest concern is that his rocket company SpaceX may fail to accomplish its foundational mission -- getting to Mars -- before he dies. “If we don't improve our pace of progress, I'm definitely going to be dead before we go to Mars,” Musk said Monday at the Satellite 2020 conference in Washington. “If it's taken us 18 years just to get ready to do the first people to orbit, we've got to improve our rate of innovation or, based on past trends, I am definitely going to be dead before Mars.” In November 2018, he told Recode that closely held SpaceX was aiming to get to Mars in 2024, and told Axios that there was a 70% chance that he personally would go. Confidential Tesla and SpaceX documents were leaked online after one of their suppliers was hacked Link: https://www.businessinsider.com/tesla-spacex-documents-leaked-online-after-supplier-hacked-2020-3 Tesla and SpaceX documents have been leaked online after one of their suppliers was hacked, TechCrunch reported. A representative for the supplier, Visser Precision, confirmed to Business Insider that company data had been accessed or stolen in a "criminal cybersecurity incident." The representative said "business is operating normally" while the company investigates the incident. Security experts told TechCrunch that the DoppelPaymer ransomware was responsible for the hack. DoppelPaymer demands a ransom in exchange for declining to publish the stolen files, and so far, nondisclosure agreements involving Tesla and SpaceX have been posted on a public website, according to TechCrunch's report. SpaceX moving on to Starship SN2 prototype after SN1 bites the dust in test Link: https://www.space.com/spacex-starship-sn1-prototype-test-failure-sn2-next.html Elon Musk seems to be taking SpaceX's recent Starship setback in stride. On Friday night (Feb. 28), the second full-size prototype of SpaceX's Mars-colonizing Starship vehicle, a variant known as the SN1, was destroyed during a pressurization test. Musk didn't immediately tweet about Friday night's incident. But the billionaire entrepreneur posted a few items early Monday morning (March 2) that suggest he's not dwelling on the SN1's demise. "So … how was your night?" read one tweet, which accompanied a video of the prototype's death. This was followed by "It's fine, we'll just buff it out," and then another tweet that said, "Where's Flextape when you need it!?" And in yet another Monday-morning tweet, Musk said that SpaceX has shifted its focus to the next prototype iteration, the SN2, which is already under construction. "We're stripping SN2 to bare minimum to test the thrust puck to dome weld under pressure, first with water, then at cryo. Hopefully ready to test in a few days," Musk wrote. DAREDEVIL 'MAD' MIKE HUGHES FAILED TO DEPLOY BACKUP CHUTES... May Have Blacked Out Link: https://www.tmz.com/2020/03/02/daredevil-mad-mike-hughes-fatal-rocket-crash-backup-parachutes/ "Mad" Mike Hughes may have blacked out and that's why he failed to deploy backup parachutes moments before his fatal rocket crash ... TMZ has learned. Mike's rep, Darren Shuster, tells TMZ ... the daredevil's launch got off to a terrible start when his parachute got snagged by a ladder next to the rocket. Mike needed a ladder because he didn't wanna be lifted into it, as they had initially prepared. When the parachute got snagged, Mike's ground control crew radioed Mike and ordered him to deploy his backup parachute. There were 2 backups on the rocket. Problem was ... the ground crew never got a response from Mike. Shuster tells us Mike's crew believes he may have blacked out with the rocket taking off at around 500 MPH. Shuster believes if Mike blacked out, it could very well explain why he never deployed his backup chute. The timing for deploying the backup chutes was also critical ... Mike would have had to deploy the backup before he hit his apex because if he was descending at too high of a speed, it would have ripped a hole in the chute. But, Mike never got the chance. Show Stuff The Dark Horde Podcast: https://www.spreaker.com/show/the-dark-horde The Dark Horde, LLC – http://www.thedarkhorde.com Twitter @DarkHorde or https://twitter.com/HordeDark TeePublic Store - Get your UBR goodies today! http://tee.pub/lic/2GQuXxn79dg UBR Truth Seekers Facebook Group: https://www.facebook.com/groups/216706068856746 UFO Buster Radio: https://www.facebook.com/UFOBusterRadio YouTube Channel: https://www.youtube.com/channel/UCggl8-aPBDo7wXJQ43TiluA To contact Manny: manny@ufobusterradio.com, or on Twitter @ufobusterradio Call the show anytime at (972) 290-1329 and leave us a message with your point of view, UFO sighting, and ghostly experiences or join the discussion on www.ufobusterradio.com For Skype Users: bosscrawler
Join the fan chat on Discord! Link: https://discord.gg/FupzWf Musk's Top Concern Now Is SpaceX Getting to Mars Before He Dies Link: https://www.bloomberg.com/news/articles/2020-03-09/elon-musk-worries-spacex-won-t-get-to-mars-before-he-dies While others worry about economies slipping into recession and markets melting down, Elon Musk's biggest concern is that his rocket company SpaceX may fail to accomplish its foundational mission -- getting to Mars -- before he dies. “If we don't improve our pace of progress, I'm definitely going to be dead before we go to Mars,” Musk said Monday at the Satellite 2020 conference in Washington. “If it's taken us 18 years just to get ready to do the first people to orbit, we've got to improve our rate of innovation or, based on past trends, I am definitely going to be dead before Mars.” In November 2018, he told Recode that closely held SpaceX was aiming to get to Mars in 2024, and told Axios that there was a 70% chance that he personally would go. Confidential Tesla and SpaceX documents were leaked online after one of their suppliers was hacked Link: https://www.businessinsider.com/tesla-spacex-documents-leaked-online-after-supplier-hacked-2020-3 Tesla and SpaceX documents have been leaked online after one of their suppliers was hacked, TechCrunch reported. A representative for the supplier, Visser Precision, confirmed to Business Insider that company data had been accessed or stolen in a "criminal cybersecurity incident." The representative said "business is operating normally" while the company investigates the incident. Security experts told TechCrunch that the DoppelPaymer ransomware was responsible for the hack. DoppelPaymer demands a ransom in exchange for declining to publish the stolen files, and so far, nondisclosure agreements involving Tesla and SpaceX have been posted on a public website, according to TechCrunch's report. SpaceX moving on to Starship SN2 prototype after SN1 bites the dust in test Link: https://www.space.com/spacex-starship-sn1-prototype-test-failure-sn2-next.html Elon Musk seems to be taking SpaceX's recent Starship setback in stride. On Friday night (Feb. 28), the second full-size prototype of SpaceX's Mars-colonizing Starship vehicle, a variant known as the SN1, was destroyed during a pressurization test. Musk didn't immediately tweet about Friday night's incident. But the billionaire entrepreneur posted a few items early Monday morning (March 2) that suggest he's not dwelling on the SN1's demise. "So … how was your night?" read one tweet, which accompanied a video of the prototype's death. This was followed by "It's fine, we'll just buff it out," and then another tweet that said, "Where's Flextape when you need it!?" And in yet another Monday-morning tweet, Musk said that SpaceX has shifted its focus to the next prototype iteration, the SN2, which is already under construction. "We're stripping SN2 to bare minimum to test the thrust puck to dome weld under pressure, first with water, then at cryo. Hopefully ready to test in a few days," Musk wrote. DAREDEVIL 'MAD' MIKE HUGHES FAILED TO DEPLOY BACKUP CHUTES... May Have Blacked Out Link: https://www.tmz.com/2020/03/02/daredevil-mad-mike-hughes-fatal-rocket-crash-backup-parachutes/ "Mad" Mike Hughes may have blacked out and that's why he failed to deploy backup parachutes moments before his fatal rocket crash ... TMZ has learned. Mike's rep, Darren Shuster, tells TMZ ... the daredevil's launch got off to a terrible start when his parachute got snagged by a ladder next to the rocket. Mike needed a ladder because he didn't wanna be lifted into it, as they had initially prepared. When the parachute got snagged, Mike's ground control crew radioed Mike and ordered him to deploy his backup parachute. There were 2 backups on the rocket. Problem was ... the ground crew never got a response from Mike. Shuster tells us Mike's crew believes he may have blacked out with the rocket taking off at around 500 MPH. Shuster believes if Mike blacked out, it could very well explain why he never deployed his backup chute. The timing for deploying the backup chutes was also critical ... Mike would have had to deploy the backup before he hit his apex because if he was descending at too high of a speed, it would have ripped a hole in the chute. But, Mike never got the chance. Show Stuff The Dark Horde Podcast: https://www.spreaker.com/show/the-dark-horde The Dark Horde, LLC – http://www.thedarkhorde.com Twitter @DarkHorde or https://twitter.com/HordeDark TeePublic Store - Get your UBR goodies today! http://tee.pub/lic/2GQuXxn79dg UBR Truth Seekers Facebook Group: https://www.facebook.com/groups/216706068856746 UFO Buster Radio: https://www.facebook.com/UFOBusterRadio YouTube Channel: https://www.youtube.com/channel/UCggl8-aPBDo7wXJQ43TiluA To contact Manny: manny@ufobusterradio.com, or on Twitter @ufobusterradio Call the show anytime at (972) 290-1329 and leave us a message with your point of view, UFO sighting, and ghostly experiences or join the discussion on www.ufobusterradio.com For Skype Users: bosscrawler
Boca Chica, Texas. 28 de febrero de 2020. El prototipo de Starship explota por segunda vez debido a un mal montaje de los tanques de combustible líquido. Elon promete que seguirán adelante con prototipos más avanzados. Mientras tanto, el Falcon Heavy, nuestro cohete favorito sigue adelante con nuevas misiones, entre ellas una de 2022 para llevar una misión de la NASA al asteroide Psyque para analizar su composición de hierro y níquel. Por último, nuestro héroe de Pretoria estuvo en un simposio de las Fuerzas Aéreas de EE.UU. hablando del futuro de la guerra. Elon Musk says ‘the fighter jet era has passed’ SpaceX Is Taking Over the Tiny Village of Boca Chica La explosión del SN1 en vídeo Elon Musk on Twitter: We’re stripping SN2 to bare minimum to test the thrust puck to dome weld under pressure, first with water, then at cryo. Hopefully, ready to test in a few days.”r SpaceX’s Falcon Heavy is getting a giant cloak for key military missions NASA Awards Launch Services Contract for the Psyche Mission Over 30 OneWeb satellites delivered from Florida to Baikonur spaceport Stealth (2005) la película de Jessica Biel que comentamos ELON está presentado por Matías S. Zavia (@matiass) y Álex Barredo (@somospostpc). Su tema original está compuesto por Nahúm García (@nahum). — Alojado en Cuonda (@cuonda)
EP 1 Sn2 - 5 hour energy by Quick and Easy Spanish
SN2 es una banda Murcia de pop que nos presenta VUELA. Se han ganado estar en la final de CAZATALENTOS 2012/2013.
VERSILIA, SONIDO TRAVEL, LA ESCALA DE RITCHER, LA RENDICION DE BRENDA, SN2, NO POTABLE CIRCO SKA, SHARP FIREFLY, BOMBASTICOS Y LOS MALVADOS, ANTHEIA... Estos son los 9 FINALISTAS DE CAZATALENTOS 2012-2013 EN el Programa de Radio ESTACION GNG de CADENA ENERGIA... Esperamos que estes atento a la fase final del 1 al 8 de febrero VOTANDO EN IVOOX por tu banda preferida de las 9 que te estamos presentando... PERMANECE ATENTO/A
In this episode, we examine the SN2 reaction. We examine what makes a good substrate, look at some problems on the virtual whiteboard, and hear about a website that has organic chemistry mechanisms.
A difficult exam question shows how visible and NMR spectroscopy related to long-term misassignment of the structure for the triphenylmethyl dimer. Evidence from 1970 shows that Friedel-Crafts propylation involves an SN2 mechanism, not a protonated cyclopropane. Assigning oxidation states from -4 to +4 to the carbon atoms of proposed starting material and product allows choosing whether a reagent that is oxidizing or reducing or neither is appropriate. Beyond belonging to the appropriate redox class, the reagent must have an appropriate mechanism. Alcohol oxidations by elemental bromine and by Cr+6 reagents are shown to involve familiar substitution, elimination, and addition mechanisms. Mechanistic understanding allows adjusting conditions to make oxidation selective. Complete course materials are available at the Open Yale Courses website: http://oyc.yale.edu This course was recorded in Spring 2011.
When electrophilic addition involves a localized carbocation intermediate, skeletal rearrangement sometimes occurs, but it can be avoided when both alkene carbons are involved in an unsymmetrical 3-center-2-electron bond, as in Markovnikov hydration via alkoxymercuration followed by reduction. Similarly a reagent that attacks both alkene carbons simultaneously by providing a nucleophilic component during electrophilic attack can avoid rearrangement, as in reactions that proceed via three-membered-ring halonium intermediates. Simultaneity in making two bonds during formation of cyclopropanes from carbenes can be demonstrated using stereochemistry. Anti-Markovnikov hydration can be achieved via hydroboration followed by oxidation with hydroperoxide. Rearrangement of the borane hydroperoxide intermediate with frontside C-O bond formation shows close orbital analogy to backside attack during SN2 substitution. Again syn-addition shows that nucleophilic attack occurs simultaneously with electrophilic attack on the alkene. Complete course materials are available at the Open Yale Courses website: http://oyc.yale.edu This course was recorded in Spring 2011.
Preliminary X-ray analysis of molecules that have been designed to favor a carbon with five bonds seemed to suggest the possibility of a pentavalent intermediate in SN2 reactions, but further analysis of these structures showed just the opposite. Boron, however, can be pentavalent in such an environment. E2, SN1 and E1 mechanisms compete with the SN2 reaction. Factors controlling E2 eliminations are illuminated by kinetic isotope effects, stereochemistry, and regiochemistry. The competition between E2 and SN2 mechanisms influence the design of synthetic schemes, including those in which carbon nucleophiles play an important role. SN1 and E1 reactions involve carbocation intermediates and thus the possibility that the carbon skeleton will rearrange. Complete course materials are available at the Open Yale Courses website: http://oyc.yale.edu This course was recorded in Spring 2011.
The nature of nucleophiles and leaving groups has strong influence on the rate of SN2 reactions. Generally a good nucleophile or strong base is a poor leaving group, but hydrogen-bonding solvents can alter nucleophile reactivity. Although amino and hydroxyl groups are poor leaving groups, they may be converted to groups that leave easily, even from bridgehead positions. Designing the preparation of a sugar analogue containing radioactive fluorine shows how understanding the SN2 mechanism enables PET scanning for medical imaging. Quantum mechanics suggests that the pentavalent carbon species on the SN2 reaction pathway is a transition state, not a stable structure. Complete course materials are available at the Open Yale Courses website: http://oyc.yale.edu This course was recorded in Spring 2011.
SN2 substitution provides an example of establishing the mechanism of a chemical reaction by disproving all the alternatives. Five general pathways are envisioned (two-step involving either pentavalent or trivalent carbon intermediates, and one-step). They can be discriminated by applying a variety of experimental tools including stereochemistry (Walden inversion), rate law (second order and pseudo first order), and the variation of rate constant with changes in the substrate (steric hindrance and ring strain), and with changes in nucleophile or leaving group. Classic experiments by Kenyon and Phillips and by Bartlett and Knox established the nature of Walden inversion. Complete course materials are available at the Open Yale Courses website: http://oyc.yale.edu This course was recorded in Spring 2011.
Fakultät für Chemie und Pharmazie - Digitale Hochschulschriften der LMU - Teil 04/06
The thesis involves three different aspects of quantum dynamics in cold and isolated molecular systems that are investigated theoretically with methods ranging from wavepacket dynamics to density matrix propagation. In the first part the efficiency of cavity sideband cooling of trapped molecules is theoretically investigated for the case in which the infrared transition between two ro-vibrational states is used as a cycling transition. The molecules are assumed to be trapped either by a radio frequency or optical trapping potential, depending on whether they are charged or neutral, and confined inside a high-finesse optical resonator that enhances radiative emission into the cavity mode. Using realistic experimental parameters and Carbonyl sulfide as a molecular representative, we show that in this setup, cooling to the trap ground state is feasible. The second part investigates femtosecond pump-probe spectroscopy of single MgH+ ions confined in an ion trap. The molecular ions are embedded in a coulomb crystal of atomic magnesium ions which are laser cooled to a few millikelvin. Single molecules are addressed by femtosecond ultraviolet laserpulses and the induced molecular processes are investigated. The simulations of the wave packet motion and dissociation behavior were used to predict the experimental parameter regime and are compared directly to the laboratory results. For this purpose a multiscale model is developed which involves the wave packet motion as well as the problem of vibrational heating occurring on a millisecond time scale under laboratory conditions. The third part investigates the gas phase SN2 collision reaction of chloride and methyl iodine. Motivated by the experimental results of Roland Wester and co-workers [Mikosch et al., Science 319, 183 (2008)], remaining questions were addressed. The collision reaction is simulated by solving the time dependent Schrödinger equation on ab initio potential energy surfaces. With the chosen reactive coordinates it is possible to reproduce the basic features of the immediate collision reaction. The internal molecular coordinates are transformed into reaction path based model which allows for an efficient numerical description of the nuclear dynamics. The energy transfer in the system is investigated and compared to the experimental results. From the new insight into the process, an intuitive concept of a dynamical barrier can be derived. Moreover the role of the spectator mode can be clarified.
SN2 reaction; SN1 reaction; elimination reactions and Zaitsev's rule; E2 reaction and cyclohexane conformation; E1 reaction; summary of reactivity; synthesis practice
Fakultät für Chemie und Pharmazie - Digitale Hochschulschriften der LMU - Teil 02/06
This work has been focused on the use of copper(I)-mediated anti-SN2’ allylic substitution reactions with non directing leaving groups. This proved to be a general and highly reliable method for the preparation of new chiral stereogenic centers in high enantioselectivity. Moreover a particular effort was made to apply this method to more complex systems, and compounds like alcohols, amines, alkenylsilanes or unsaturated nitriles could be successfully prepared in their enantiomerically enriched form.