A K<sup>+</sup>-promoted Diels–Alder reaction by using a self-assembled macrocyclic boronic ester containing two crown ether moieties
作者:Kosuke Ono、Morikazu Niibe、Nobuharu Iwasawa
DOI:10.1039/c9sc01597c
日期:——
dienes is achieved in the presence of a self-assembled macrocyclic boronicester [2+2]crown containing two crown ether moieties. The reaction rate is remarkably accelerated (up to 206-fold) compared to that in the absence of the promoter. Furthermore, the reaction proceeds regioselectively to yield an internal adduct. The self-assembly protocol was also demonstrated.
AK +促进的 1,4,9,10-蒽醌与各种二烯的 Diels-Alder 反应是在包含两个冠醚部分的自组装大环硼酸酯[2+2]冠存在下实现的。与不存在促进剂的情况相比,反应速率显着加快(高达206倍)。此外,反应进行区域选择性,产生内加合物。还演示了自组装协议。
Expanding the Chiral Monoterpene Pool: Enantioselective Diels–Alder Reactions of α-Acyloxy Enones
作者:Skyler D. Mendoza、Michael Rombola、Yujia Tao、Stephan J. Zuend、Roland Götz、Martin J. McLaughlin、Sarah E. Reisman
DOI:10.1021/acs.orglett.2c01343
日期:2022.6.3
α-acyloxy enones has been developed to synthesize chiral oxidized cyclohexenes. Yttrium(III) triflate, in conjunction with a chiral pyridinebisimidazoline (PyBim) ligand, was found to catalyze the asymmetric [4 + 2] cycloaddition with a variety of dienes and α-acyloxy enone dienophiles. Using this method, terpinene-4-ol, a key intermediate in the synthesis of commercial herbicide cinmethylin, can be prepared
Viktorov; Zubritskii, Russian Journal of Organic Chemistry, 1999, vol. 35, # 12, p. 1755 - 1765
作者:Viktorov、Zubritskii
DOI:——
日期:——
A Practical, Two-Step Synthesis of 2-Substituted 1,3-Butadienes
作者:Sushmita Sen、Swapnil Singh、Scott McN. Sieburth
DOI:10.1021/jo802737x
日期:2009.4.3
A two-step procedure for preparing 2-alkyl-1,3-butadienes is described. Cuprate addition to commercially available 1,4-dibromo-2-butene yields 3-alkyl-4-bromo-1-butene, a product Of S(N)2' substitution. Dehydrohalogenation gives 2-alkyl-1,3-butadienes.