(1R,2R)-1-((E)-Styryl)-2-methylcyclopropane 在 250 o C 外消旋并异构化为 6-苯基六-1,4-(Z)-二烯和 3-苯基-的四种异构体4-甲基环戊烯。从外消旋化和结构异构化的测量速率常数,以及四种 3-苯基-4-甲基环戊烯的相对量随时间变化的信息,四种立体化学不同路径对这种乙烯基环丙烷重排的相对贡献是发现为 60% si、10% ar、19% sr 和 11% ai
Enantiodivergent Pd-catalyzed C–C bond formation enabled through ligand parameterization
作者:Shibin Zhao、Tobias Gensch、Benjamin Murray、Zachary L. Niemeyer、Matthew S. Sigman、Mark R. Biscoe
DOI:10.1126/science.aat2299
日期:2018.11.9
The staying power of electron-poor ligands The venerable Suzuki coupling reaction originally used palladium to pair up unsaturated carboncenters. The protocol has been widely extended to chiral saturated alkyl carbons, but control over product stereochemistry is a pressing challenge. Zhao et al. systematically studied how the properties of the phosphine ligands that are coordinated to the catalyst
The nucleoside transport inhihitor 6-[(4-nitrobenzyl)thio]-9-(beta-D-ribofuranosyl)purine, NBMPR, has been used successfully in photoaffinity labeling. We have studied the mechanism for photocleavage of the benzyl-sulfur bond by using substituted benzyl phenyl sulfides as analogues of NBMPR. This has enabled us to enhance the photoreactivity of the benzyl-sulfur bond. We have also performed ,,radical clock'' studies with a hexenyl side chain to trap reactive intermediates. The mechanistic interpretation from the substituent and side chain studies is that the benzyl-sulfur moiety is photocleaved via a homolytic pathway.
Organoyttrium-catalyzed cyclization of substituted 1,5- and 1,6-dienes
作者:Gary A. Molander、John O. Hoberg
DOI:10.1021/ja00034a061
日期:1992.4
Perrott, Allyson L.; Arnold, Donald R., Canadian Journal of Chemistry, 1992, vol. 70, # 1, p. 272 - 279
作者:Perrott, Allyson L.、Arnold, Donald R.
DOI:——
日期:——
Stereochemistry of the thermal isomerizations of (1R,2R)-1-[(E)-styryl]-2-methylcyclopropane to 3-phenyl-4-methylcyclopentenes
作者:John E. Baldwin、Samuel Bonacorsi
DOI:10.1021/ja00076a021
日期:1993.11
(1R,2R)-1-((E)-Styryl)-2-methylcyclopropane at 250 o C racemizes and isomerizes to 6-phenylhexa-1,4-(Z)-diene and to the four isomers of 3-phenyl-4-methylcyclopentene. From the measured rate constants for racemization and for structural isomerizations, and from information on the relative amounts of the four 3-phenyl-4-methylcyclopentenes as a function of time, the relative contributions of the four
(1R,2R)-1-((E)-Styryl)-2-methylcyclopropane 在 250 o C 外消旋并异构化为 6-苯基六-1,4-(Z)-二烯和 3-苯基-的四种异构体4-甲基环戊烯。从外消旋化和结构异构化的测量速率常数,以及四种 3-苯基-4-甲基环戊烯的相对量随时间变化的信息,四种立体化学不同路径对这种乙烯基环丙烷重排的相对贡献是发现为 60% si、10% ar、19% sr 和 11% ai