Absolute Kinetic Studies of Carbene Reactions

卡宾反应的绝对动力学研究

• 批准号: 9109044
• 负责人: Robert Moss
• 金额: $ 35万
• 依托单位: Rutgers University New Brunswick
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-01-01 至 1995-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9109044&HistoricalAwards=false
• 关键词: Absolute; Kinetic; Studies; Carbene; Reactions

A study of carbenes and related reactive intermediates by laser flash photolysis will be conducted. Spectroscopic and kinetic measurements of these highly reactive intermediates in solution will be made. The research projects will include investigation of: (1) the properties of nucleophilic carbenes; (2) the kinetics of carbene/metal salt reactions (carbenoid formation); (3) the properties of "push pull" carbenes as well as pyridyl and pyridinium carbenes; (4) the effects of fluoro and methoxy substituents in modulating intramolecular carbene rearrangements; and (5) the fragmentation of oxycarbenes to carbocations. These studies will be of particular importance in providing insight and understanding for reactions that are characterized by low activation energy barriers. %%% This grant from the Organic Dynamics Program supports the continuing work of Professor Robert A. Moss at Rutgers University. These studies will be centered around the production and reactions of carbenes, which are species that contain a carbon atom with two formal bonds rather than four bonds as found in stable carbon compounds. Carbenes are reactive intermediates that are very short-lived. Special flash laser techniques will be employed to observe these reactive intermediates and to study the rate at which they react. Carbenes can undergo reaction to give other reactive intermediates. For example, carbenes can react with lithium chloride to generate an adduct called a carbenoid with the normal complement of four bonds. With appropriate substitution, carbenes can give another reactive intermediate, a carbocation, which contains a carbon with three bonds and a net one unit of positive charge. These reactions will provide a means to study some of the important reactive intermediates in organic chemistry.

将通过激光闪光光解对碳烯和相关反应性中间体进行研究。这些高反应性中间体的光谱和动力学测量将在溶液中进行。研究项目将包括以下研究：（1）亲核癌的特性； （2）碳/金属盐反应的动力学（卡宾形成）； （3）“推拉”卡宾斯以及吡啶基和吡啶carbenes的特性； （4）氟和甲氧化取代基在调节分子内卡宾重排的影响； （5）氧气对碳的破碎。这些研究在提供以低活化能屏障为特征的反应的洞察力和理解方面尤其重要。 %% %%来自有机动力学计划的这笔赠款支持罗格斯大学罗伯特·A·莫斯教授的持续工作。这些研究将集中在卡宾斯的生产和反应围绕，这些物种包含一个具有两个正式键的碳原子，而不是稳定的碳化合物中发现的四个键。卡宾斯是反应性的中间体，它们是非常短暂的。将采用特殊的闪光激光技术来观察这些反应性中间体并研究它们反应的速度。 碳烯可以反应以产生其他反应性中间体。例如，卡宾斯可以与氯化锂反应，以产生一种称为类carbenoid的加合物，其正常补体的四个键。通过适当的替代，卡宾斯可以给出另一个反应性中间体，一个碳酸盐，其中包含具有三个键的碳和一个净一个正电荷的碳。这些反应将提供一种研究有机化学中一些重要的反应性中间体的方法。