Modeling and Experiment Reveal an Unexpected Stereoelectronic Effect on Conformation and Scalar Couplings of α-Aminoorganostannanes, with Possible Relevance to the Tin−Lithium Exchange Reaction
- 1 October 2003
- journal article
- research article
- Published by American Chemical Society (ACS) in The Journal of Organic Chemistry
- Vol. 68 (22) , 8480-8484
- https://doi.org/10.1021/jo034948y
Abstract
The solution conformation of N-methyl-2-(tributylstannyl)piperidines has been determined through the use of vicinal 119Sn-13C coupling constants, revealing a conformational distortion caused by an unexpected stereoelectronic effect in some cases. Specifically, the "equatorial" conformer is distorted into a half-chair, in which the nitrogen lone pair eclipses the C-Sn bond. This distortion, which "costs" approximately 1 kcal/mol, correlates with a conformational dependence of geminal 119Sn-15N couplings and a possible correlation with reactivity in the tin-lithium exchange reaction.Keywords
This publication has 25 references indexed in Scilit:
- Synthesis and Reactivity of Dipole-Stabilized but Unchelated α-AminoorganolithiumsThe Journal of Organic Chemistry, 2000
- Unusual Conformational Effect in α-AminoorganostannanesOrganic Letters, 1999
- Anionic Cyclizations of α-Aminoorganolithiums. Determination of the Stereoselectivity at the Carbanion Center and the Synthesis of (+)-PseudoheliotridaneJournal of the American Chemical Society, 1996
- Alkylation of 2-lithio-N-methylpiperidines and -pyrrolidines: scope, limitations, and stereochemistryThe Journal of Organic Chemistry, 1995
- 2-Lithio-N-methylpiperidine and 2-lithio-N-methylpyrrolidine: configurationally and chemically stable unchelated .alpha.-aminoorganolithiumsJournal of the American Chemical Society, 1993
- Total synthesis of the marine polypropionate (+)-muamvatin. A configurational model for siphonariid metabolitesJournal of the American Chemical Society, 1993
- Stereochemical studies on chiral, nonconjugated, nitrogen-substituted carbanions generated by tin-lithium exchangeJournal of the American Chemical Society, 1991
- Oxidatively assisted nucleophilic substitution/elimination of alkyl iodides in alcoholic media. A further studyThe Journal of Organic Chemistry, 1982
- Use of the thallium trinitrate catalyzed rearrangement of ketones in the synthesis of an acidic morphinan derivativeThe Journal of Organic Chemistry, 1978
- Proton magnetic resonance study of the indole NH resonances of lysozyme. Assignment, deuterium exchange kinetics, and inhibitor bindingJournal of the American Chemical Society, 1971