Experimental Diels-Alder Reactivities of Cycloalkenones and Cyclic Dienes Explained through Transition-State Distortion Energies
作者:Robert S. Paton、Seonah Kim、Audrey G. Ross、Samuel J. Danishefsky、K. N. Houk
DOI:10.1002/anie.201103998
日期:2011.10.24
Quantum chemical calculations are used to investigate the experimentally measured reactivities of cyclicdienes and cycloalkenones in the Diels–Alder reaction. The interaction energies (red) are nearly constant; differences arise in changes in distortionenergies of both dienophile (blue) and diene (green; see picture, Ea=activation energy; values in kcal mol−1).
量子化学计算用于研究Diels-Alder反应中环二烯和环烯酮的反应活性。相互作用能(红色)几乎恒定;亲二烯体(蓝色)和二烯(绿色;见图片,E a =活化能; kcal mol -1的值)的变形能变化会产生差异。
Chiral Oxazaborolidine−Aluminum Bromide Complexes Are Unusually Powerful and Effective Catalysts for Enantioselective Diels−Alder Reactions
作者:Duan Liu、Eda Canales、E. J. Corey
DOI:10.1021/ja068637r
日期:2007.2.1
acid catalyst than protonated 1 (i.e., 2) for enantioselectiveDiels−Alderreactions. Only 4 mol % of catalyst 3 is required to achieve yields and enantiomeric purities of 90% over a broad range of achiraldienes and dienophiles. The ligand from which 3 is derived can be recovered easily and with high efficiency. The method is illustrated by 22 examples.
Broad-Spectrum Enantioselective Diels−Alder Catalysis by Chiral, Cationic Oxazaborolidines
作者:Do Hyun Ryu、Thomas W. Lee、E. J. Corey
DOI:10.1021/ja027468h
日期:2002.8.1
catalysts for Diels-Alder addition of cyclopentadiene to a wide variety of dienophiles. Adducts have been obtained in excellent yield and enantioselectivity from alpha,beta-unsaturated esters, lactones, and cyclic ketones. The absolute facial selectivity for each of these substrates follows a common pattern which differs from that observed with alpha,beta-enals. The different reaction channels can be
Effect of micellar medium on photoannelation vs energy transfer in the system excited cyclohex-2-en-1-one-cyclopentadiene
作者:M.Suresh Kumar、Jampani Madhusudana Rao
DOI:10.1016/s0040-4020(01)87845-5
日期:1990.1
The relative ratio of enone-CPD adducts and C15H18 formed in the photochemical reaction between cyclohex-2-en-1-one and its 4,4 dimethyl derivative and CPD in different media suggest that an exciplex is responsible for 2+2 photoannelation and energy transfer and a transoid or twisted enone for photo Diels-Alder reaction.
环己-2-烯-1-酮及其4,4二甲基衍生物与CPD在不同介质中的光化学反应中形成的烯酮-CPD加合物和C 15 H 18的相对比例表明,激基复合物是2 + 2的原因。光退火和能量转移,以及用于光Diels-Alder反应的透明或扭曲的烯酮。
Diels-Alder reactions of cycloalkenones. 14. Endo diastereoselectivity of 2-cyclohexenones in reactions with cyclopentadiene
作者:E. Charles Angell、Francesco Fringuelli、Ming Guo、Lucio Minuti、Aldo Taticchi、Ernest Wenkert