Concerning the 1,5-stereocontrol in tin(iv) chloride promoted reactions of 4- and 5-alkoxyalk-2-enylstannanes: trapping intermediate allyltin trichlorides using phenyllithium
作者:Lindsay A. Hobson、Eric J. Thomas
DOI:10.1039/c2ob25765c
日期:——
riphenyl)stannane 9 generated an allyltin trichloride that reacted with aldehydes to give the (Z)-1,5-syn-6-benzyloxy-5-methylhex-3-en-1-ols 23 and was trapped by phenyllithium to give syn-5-benzyloxy-4-methylpent-1-en-3-yl(triphenyl)stannane 24. Similar stereoselectivity was observed for tin(IV) chloride promoted reactions of this syn-5-benzyloxy-4-methylpent-1-en-3-yl(triphenyl)stannane 24 with aldehydes
Using the comparison of steric versus electronic effects to infer mechanistic information in stepwise electrophilic addition reactions involving three-membered cyclic intermediates
作者:Donna J. Nelson、Raman Soundararajan
DOI:10.1016/s0040-4039(00)82306-0
日期:1988.1
Correlations of IP's versus relative reactivities or formation constants of reactions of alkenes with ArSCl, MeCO3H, Ag+, or HgCl2 reveal that complexation reactions show steric dependence, that additions with the first step rate-determining are sterically independent, and that those with the second step rate-determining are sterically dependent.
Photocatalytic Asymmetric Epoxidation of Terminal Olefins Using Water as an Oxygen Source in the Presence of a Mononuclear Non-Heme Chiral Manganese Complex
作者:Duyi Shen、Claudio Saracini、Yong-Min Lee、Wei Sun、Shunichi Fukuzumi、Wonwoo Nam
DOI:10.1021/jacs.6b10836
日期:2016.12.14
epoxidation of terminal olefins using a mononuclear non-heme chiral manganese catalyst, [(R,R-BQCN)MnII]2+, and water as an oxygen source yields epoxides with relatively high enantioselectivities (e.g., up to 60% enantiomeric excess). A synthetic mononuclear non-heme chiral Mn(IV)-oxo complex, [(R,R-BQCN)MnIV(O)]2+, affords similar enantioselectivities in the epoxidation of terminal olefins under stoichiometric
Regioselective Carbonylation of <i>trans</i>-Disubstituted Epoxides to β-Lactones: A Viable Entry into <i>syn</i>-Aldol-Type Products
作者:Michael Mulzer、Bryan T. Whiting、Geoffrey W. Coates
DOI:10.1021/ja405151n
日期:2013.7.31
reported for the regioselective carbonylation of trans-disubstituted epoxides to cis-β-lactones. The two catalysts display high and opposing selectivities, which generally are difficult to achieve for this class of epoxides. The resulting β-lactones are well-defined precursors for a wide variety of aldol-type compounds. Altogether, carbonylation of disubstituted epoxides is established as a viable and
Enantioselective hydrolysis of aryl, alicyclic and aliphatic epoxides by Rhodotorula glutinis
作者:Carel A.G.M. Weijers
DOI:10.1016/s0957-4166(97)00012-8
日期:1997.2
Enantioselective epoxide hydrolysis by yeasts has been demonstrated for the hydrolysis of several aryl, alicyclic and aliphatic epoxides by a strain of Rhodotorula glutinis. High enantioselectivity was obtained in the hydrolysis of methyl substituted arylryl and aliphatic epoxides whereas selectivity towards terminal epoxides in all cases was lower. Homochiral vicinal diols were formed from several