Ozonolysis of Bicyclic 1,2-Dioxines: Initial Scope and Mechanistic Insights
作者:Nicole M. Cain、Edward R. T. Tiekink、Dennis K. Taylor
DOI:10.1021/jo3001518
日期:2012.4.20
The ozonolysis of bicyclic 1,2-dioxines was investigated using a variety of 1,4-disubstituted 1,2-dioxines along with a 1,3-dialkyl and steroidal example, with yields ranging from moderate to excellent. Two different pathways were observed upon reaction of the 1,4-disubstituted 1,2-dioxines with ozone; one pathway saw the “expected” results, that is, cleavage of the olefinic moiety with generation
Unexpectedly Similar Charge Transfer Rates through Benzo-Annulated Bicyclo[2.2.2]octanes
作者:Randall H. Goldsmith、Josh Vura-Weis、Amy M. Scott、Sachin Borkar、Ayusman Sen、Mark A. Ratner、Michael R. Wasielewski
DOI:10.1021/ja8004623
日期:2008.6.18
A 4-(pyrrolidin-1-yl)phenyl electron donor and 10-cyanoanthracen-9-yl electron acceptor are attached via alkyne linkages to the bridgehead carbon atoms of bicyclo[2.2.2]octane and all three benzo-annulated bicyclo[2.2.2]octanes. The sigma-system of bicyclo[2.2.2]octane provides a scaffold having nearly constant bridge geometry on which to append multiple, weakly interacting benzo pi-bridges, so that
4-(吡咯烷-1-基)苯基电子供体和10-氰基蒽-9-基电子受体通过炔键连接到双环[2.2.2]辛烷和所有三个苯并环化双环[2.2的桥头碳原子.2]辛烷。双环 [2.2.2] 辛烷的 sigma 系统提供了一个具有几乎恒定桥几何形状的支架,在该支架上可以附加多个弱相互作用的苯并 pi 桥,因此递增数量的 pi 桥对电子转移速率的影响可以被研究。令人惊讶的是,通过甲苯中的瞬态吸收光谱法测量的光致电荷转移率显示增加桥 pi 系统的数量没有任何好处,这表明通过 sigma 系统的主要传输。更令人惊讶的是,由于苯并环化,sigma 系统经历的杂交的显着变化似乎也对电荷转移速率没有影响。自然键轨道分析适用于 sigma 和 pi 通信路径。在 2-甲基四氢呋喃 (MTHF) 中获得的瞬态吸收光谱表明,苯并环化分子之间存在微小差异,这归因于溶剂化的变化。将 MTHF 溶液冷却至玻璃态后,所有电荷转移速
AGENTS AFFECTING LIPID METABOLISM: XIII. THE SYNTHESIS OF 1,4-DISUBSTITUTED BICYCLO[2.2.2]OCTANE DERIVATIVES
作者:L. G. Humber、G. Myers、L. Hawkins、C. Schmidt、M. Boulerice
DOI:10.1139/v64-422
日期:1964.12.1
Several routes to the synthesis of 1,4-disubstituted bicyclo[2.2.2]octanes have been explored and the syntheses of several such derivatives are reported. The 1,4-disubstituted bicyclo[2.2.2]-octane nucleus could not be prepared through an elimination reaction on a corresponding 2,5-disubstituted derivative or by the Diels–Alder reaction of various dienophiles with dimethyl 1,3-cyclohexadiene-1,4-dicarboxylate
Difunctionalised arene Ru6C cluster compounds with electron-withdrawing groups
作者:Andrew J. Edwards、Brian F. G. Johnson、Simon Parsons、Douglas S. Shephard
DOI:10.1039/dt9960003837
日期:——
Thermolysis of [Ru6C(CO)17]1 with dimethyl cyclohexa-1,3-diene-1,4-dicarboxylate [C6H6(CO2Me)2-1,4] in dibutyl ether gave two isomeric cluster compounds [Ru6C(CO)14(η6-C6H4(CO2Me)2-1,4]2 and [Ru6C(CO)14(µ3-η2:η2:η2-C6H4(CO2Me)2-1,4)]3. The solid-state molecular structures of 2 and 3 have been established by low-temperature single-crystal X-ray diffraction analysis. These constitute the first example of co-ordination isomerism for the Ru6C(CO)14 unit with respect to a specific arene. In 2 the arene is η6 bonded to a single ruthenium atom whereas in 3 the arene is bonded in the µ3 mode to a triangular Ru3 face of the octahedral cluster unit. The solid-state structure of 3 is comprised of two rotamers along with two molecules of dichloromethane solvate. The solid-state architectures of 2 and 3 were also examined. The bifunctionalised arene ligand in 2 and 3 has the potential for further organic chemistry at these sites including possible copolymerisation with primary/secondary diamines.
On the purported synthesis of a bicyclo[2.2.1]heptene diester by reaction of diazomethane with dimethyl 1,3-cyclohexadiene-1,4-dicarboxylate
作者:Andrew S. Kende、Xiao-Chuan Guo
DOI:10.1016/s0040-4039(00)02239-5
日期:2001.2
Addition of diazomethane to dimethyl 1,3-cyclohexadiene-1,4-dicarboxylate, followed by thermolysis at 140°C, had been reported to yield a bicyclo[2.2.1]heptene diester. This report is not correct. The products are now shown to be a diene diester, a cyclopropane and an exo-methylene diester.