Quantitative Analyses of the Four Isomers of 3,4-Diphenylcyclopentene by Chiral Gas Chromatography
摘要:
The four isomers of 3,4-diphenylcyclopentene are well resolved by chiral gas chromatography on a Cyclodex B column, eluting in the ordered sequence (3S,4R), (3R,4S), (3S,4S), and(3R,4R). Absolute stereochemical assignments were made through chemical correlations relating the 3,4-diphenylcyclopentenes with a known reference compound, (1S,2S)-(+)-cis-2-phenylcyclopentanol.
A palladium-catalyzed conjugate addition of arylboronicacids to α-substituted cyclic enones was developed to give α,β-disubstituted ketones with high diastereoselectivity. Mechanistic investigation showed that the high diastereoselectivity was realized through epimerization.
Weidlich; Meyer-Delius, Chemische Berichte, 1941, vol. 74, p. 1195,1209
作者:Weidlich、Meyer-Delius
DOI:——
日期:——
Ring expansion of cyclobutanones to cyclopentanones via .alpha.-lithioalkyl aryl sulfoxides and selenoxides
作者:Robert C. Gadwood、Ishwar M. Mallick、Amy J. DeWinter
DOI:10.1021/jo00381a013
日期:1987.3
Asymmetric Carbon−Carbon Bond Formations by Conjugate Additions of Lithiated <i>N</i>-Boc Allylic Amines to Nitroalkenes: Enantioselective Synthesis of Functionalized Cyclopentanoids
作者:Timothy A. Johnson、Michael D. Curtis、Peter Beak
DOI:10.1021/ol026277g
日期:2002.8.1
[GRAPHICS]Allylic organolithiums generated by enantioselective deprotonation of N-Boc-N-(p-methoxyphenyl) allylic amines undergo conjugate additions with nitroalkenes to provide enecarbamates containing two contiguous stereogenic centers in good yields with high diastereoselectivities and enantioselectivities. Further elaboration of these adducts to enantioenriched substituted cyclopentanones and aminocyclopentanes is reported.