22906-19-0Relevant articles and documents
Formation of Cyclopropanes via Activation of (γ-Methoxy)alkyl Gold(I) Complexes with Lewis Acids
Kim, Nana,Widenhoefer, Ross A.
, p. 3160 - 3167 (2020/09/12)
Treatment of the gold 3-methoxy-3-phenylpropyl complex (P)AuCH2CH2CH(OMe)Ph [P = P(t-Bu)2o-biphenyl] with AlCl3 at -78 °C led to the immediate (≤5 min) formation of a 4:1 mixture of phenylcyclopropane and (1-methoxypropyl)benzene in 86 ± 5% combined yield. Lewis acid activation of the stereochemically pure isotopomer erythro-(P)AuCH2CHDCH(OMe)Ph led to the formation of cis-2-deuterio-1-phenylcyclopropane in 84 ± 5% yield as a single stereoisomer, which established that cyclopropanation occurred with inversion of the γ-stereocenter. Similarly, ionization of the stereochemically pure cyclohexyl gold complex cis-(P)AuCHCH2CH(OMe)CH2CH2CH2 at -78 °C formed bicyclo[3.1.0]hexane in 82% ± 5% yield, which validated a low energy pathway for cyclopropanation involving inversion of the α-stereocenter. Taken together, these observations are consistent with a mechanism for cyclopropane formation involving backside displacement of both the Cγleaving group and the Cα (L)Au+ fragment via a W-shaped transition state.
The Lithium Diisopropylamide-induced Fragmentation of 1,3-Dithiolane Derivatives of Several Ketones Having α-Hydrogen
Ikehira, Hideyuki,Tanimoto, Shigeo,Oida, Tatsuo
, p. 2537 - 2538 (2007/10/02)
The reaction of 1,3-dithiolane derivatives of ketones having a-hydrogen with lithium diisopropylamide results in fragmentation to the corresponding thioketone followed by further conversion in a few steps to the other intermediate species which, on trapping with alkyl halide, leads to a vinylic sulfide and/or a sulfide bearing a secondary alkyl group.
