Carbon-hydrogen activation mechanisms and regioselectivity in the cyclometalation reactions of bis(pentamethylcyclopentadienyl)thorium dialkyl complexes
作者:Joseph W. Bruno、Gregory M. Smith、Tobin J. Marks、C. Kay. Fair、Arthur J. Schultz、Jack M. Williams
DOI:10.1021/ja00261a009
日期:1986.1
contribution reports on the syntheses, structures and cyclometalation reactions of a series of bis(pentamethylcyclopentadienyl)thorium dialkyl complexes of the type Cp'/sub 2/ThR/sub 2/ (Cp' = eta/sup 5/-C/sub 5/Me/sub 5/). It focuses upon the pathway of C-H ..-->.. C'-H hydrogen atom transfer, hydrogen atom positions in the ground states of Cp'/sub 2/Th(CH/sub 2/CMe/sub 3/)/sub 2/ by single-crystal neutron
An extraordinary isotope effect in a carbene rearrangement
作者:Robert A Moss、Guo-Jie Ho、Weiguo Liu、Claudia Sierakowski
DOI:10.1016/s0040-4039(00)74240-7
日期:1992.7
The kinetic isotope effect for the 1,2∼H/1,2∼D shift in neopentylfluorocarbenes 2a–2c is about 5.
新戊基氟卡宾2a–2c中1,2〜H / 1,2〜D位移的动力学同位素效应约为5。
Enantiomerically pure dihydropyrimidinones as reagents and auxiliaries for asymmetric synthesis
作者:Kent S. Chu、George R. Negrete、Joseph P. Konopelski、Frederick J. Lakner、Nam Tae Woo、Marilyn M. Olmstead
DOI:10.1021/ja00031a039
日期:1992.2
determined by X-ray crystallographic analysis, demonstrates significant pyramidalization at the C4 (carbonyl) and N1 centers, with little evidence of conjugation of N1 with the α,β-unsaturated (vinylogousurea) system