Enantioselective Heck-Matsuda Arylations through Chiral Anion Phase-Transfer of Aryl Diazonium Salts
作者:Carolina M. Avila、Jigar S. Patel、Yernaidu Reddi、Masato Saito、Hosea M. Nelson、Hunter P. Shunatona、Matthew S. Sigman、Raghavan B. Sunoj、F. Dean Toste
DOI:10.1002/anie.201702107
日期:2017.5.15
seven‐membered ring alkenes and aryl diazonium salts is presented. High yields and enantioselectivities were achieved using Pd0 and chiral anion co‐catalysts, the latter functioning as a chiral anion phase‐transfer (CAPT) reagent. For certain substrate classes, the chiral anion catalysts were modulated to minimize the formation of undesired by‐products. More specifically, BINAM‐derived phosphoric acid catalysts
Stereoselective epoxidation of cyclic alkenes using m-CPBA and Oxone®/trifluoroacetone — A comparison
作者:Simon E. de Sousa、Peter O'Brien、Christopher D. Pilgram、Daniel Roder、Timothy D. Towers
DOI:10.1016/s0040-4039(98)02320-x
日期:1999.1
A comparison of the observed diastereoselectivity of epoxidation of cyclic alkenes using m-CPBA and Oxone®/trifluoroacetone is reported. The results indicate that dioxiraneepoxidations are sterically controlled and provide a crude model for determination of whether hydrogen bonding is operating in the m-CPBA epoxidations.
Synthesis and enantioselective rearrangement of 4-amino-substituted cyclopentene oxides
作者:Peter O'Brien、Timothy D. Towers、Matthias Voith
DOI:10.1016/s0040-4039(98)01821-8
日期:1998.10
Several N-mono- and diprotected alkenes have been prepared and the, stereoselectivity of their epoxidation has been investigated: N-monoprotected alkenes give cis epoxides preferentially (due to hydrogen bonding directed epoxidations) whereas N-diprotected alkenes produce trans epoxides exclusively (due to steric effects). Chiral lithium amide base-mediated rearrangement of a cis-monoprotected epoxide generated the corresponding amino-cyclopentenol in good yield and with an enantiomeric excess of 60%. (C) 1998 Elsevier Science Ltd. All rights reserved.