Enantioselective, Catalytic One‐Pot Synthesis of
<i>γ</i>
‐Butyrolactone‐Based Fragrances
作者:Ceyda Kumru、Thomas Classen、Jörg Pietruszka
DOI:10.1002/cctc.201801040
日期:2018.11.7
Herein the preparative (1 g scale), stereoselective syntheses of various alkyl‐substituted γ‐butyrolactone fragrances 1 is described. The α,β‐unsaturated γ‐keto esters 2 as starting materials were synthesized by a Horner‐Wadsworth‐Emmons reaction and are further reduced by an ene reductase and alcohol dehydrogenase in a one‐pot enzyme cascade to nine desired γ‐butyrolactones 1, among them whisky (1 c)
Dichotomous regiochemistry of aldehyde and ketone in the reaction with dithio-substituted crotyllithium
作者:Jim Min Fang、Bor Cherng Hong、Li Fan Liao
DOI:10.1021/jo00381a026
日期:1987.3
Enhancement of enantiocontrol/diastereocontrol in catalytic intramolecular cyclopropanation and carbon-hydrogen insertion reactions of diazoacetates with Rh2(4S-MPPIM)4
作者:Michael P. Doyle、Qi-Lin Zhou、Alexey B. Dyatkin、Daniel A. Ruppar
DOI:10.1016/0040-4039(95)01561-u
日期:1995.10
Dirhodium(II) tetrakis[methyl 1-(3-phenylpropanoyl)imidazolidin-2-one-4(S)-carboxylate], Rh-2(4S-MPPIM)(4), provides significant enhancement in enantiocontrol for intramolecular cyclopropanation reactions of allylic diazoacetates and optimal enantiocontrol/diastereocontrol for intramolecular C-H insertion reactions of secondary alkyl diazoacetates.
Regio- and diastereoselective reactions of dithio-substituted crotyllithium and aldehydes
作者:Jim Min Fang、Li Fan Liao、Ber Cherng Hong
DOI:10.1021/jo00364a045
日期:1986.7
A stereochemical study on the intramolecular hydrosilylation of α,β-unsaturated esters
作者:Scott E. Denmark、David C. Forbes
DOI:10.1016/s0040-4039(00)61182-6
日期:1992.8
The intramokcular hydrosilylation of several 3-methyl-4-siloxy-2-butenoates afforded cis disubstituted lactones after desilylation. The diastereoinduction was sensitive to the bulk of the allylic substituent, but not to the groups on silicon. The origin of asymmetric induction is believed to be the A1,2 strain from the beta-methyl group.