Bromide and iodide anions switch hydrogen-bonding patterns in otherwise isostructural dimethanol solvates N-methyl-1,4-diazabicyclo[2.2.2]octanium bromide (dabcoCH3Br·2CH3OH) and analogous iodide (dabcoCH3I·2CH3OH), both synthesized in the high-pressure version of the Menshutkin reaction at 1.2 and 2.4 GPa, respectively. The magnitudes of the high pressure triggering these reactions correspond to identical molecular volumes of both solvates.
High pressure used for producing a new solvate of 1,4-diazabicyclo[2.2.2]octane hydroiodide
作者:A. Olejniczak、M. Podsiadło、A. Katrusiak
DOI:10.1039/c5nj01654a
日期:——
Above 3.1 GPa, the solvate with water and methanol is formed, which cannot be obtained at normal pressure.
在3.1 GPa以上的压力下,会形成含水和甲醇的溶剂,这在常压下无法获得。
Methods and compounds for the preparation of carbacephems
申请人:Eli Lilly and Company
公开号:US05521307A1
公开(公告)日:1996-05-28
A chiral process for preparing compounds of the formula: ##STR1## from a compound of the formula: ##STR2## in which the compound formula (IV) is reacted with trimethylsilyl iodide to remove the chiral auxiliary at the 7-position and the carboxy protecting group. The process allows for the retention of the amino and carboxy protecting groups throughout the preparation of Compound IV. Also disclosed are novel intermediates.
Chiral intermediates for the preparation of carbacephems
申请人:Eli Lilly and Company
公开号:US05700933A1
公开(公告)日:1997-12-23
The present invention is directed to azetidinone compounds of the following formula: ##STR1## which are useful as intermediates to carbacephalosporins: ##STR2## These carbacephalosporins are useful as antibacterials.