Stoichiometric and Catalytic C−C and C−H Bond Formation with B(C<sub>6</sub>
F<sub>5</sub>
)<sub>3</sub>
via Cationic Intermediates
作者:Yashar Soltani、Lewis C. Wilkins、Rebecca L. Melen
DOI:10.1002/anie.201704789
日期:2017.9.18
concomitant C−H or C−C bondformation. The activation of alkyne‐containing substrates with B(C6F5)3 enabled the first catalytic intramolecular cyclizations of carboxylic acid substrates using this Lewis acid. In addition, intramolecular cyclizations of esters enable C−C bondformation as catalytic B(C6F5)3 can be used to effect formal 1,5‐alkyl migrations from the ester functional groups to unsaturated carbon–carbon
这项工作展示了一种新的催化环化反应,该反应使用高度路易斯酸的硼烷并伴有CH或CC键的形成。用B(C 6 F 5)3活化含炔的底物使得能够使用该路易斯酸对羧酸底物进行第一个催化的分子内环化反应。此外,酯的分子内环化使CC键形成为催化性B(C 6 F 5)3。可用于实现从酯官能团到不饱和碳-碳骨架的正式1,5-烷基迁移。该无金属方法用于在相对温和的条件下以极高的收率和极好的原子效率催化形成复杂的二氢吡喃酮和异香豆素。
Bismuth-Catalyzed Intramolecular Carbo-oxycarbonylation of 3-Alkynyl Esters
作者:Kimihiro Komeyama、Keita Takahashi、Ken Takaki
DOI:10.1021/ol8019567
日期:2008.11.20
Borderline metal complexes, especially Bi(OTf)3, efficiently catalyze the carbo-oxycarbonylation of alkynyl esters to form multisubstituted lactones in moderate to high yields.
Bismuth-catalyzed Intramolecular Hydro-oxycarbonylation of Alkynes
作者:Kimihiro Komeyama、Keita Takahashi、Ken Takaki
DOI:10.1246/cl.2008.602
日期:2008.6.5
Bi(OTf)3 was found to be a good catalyst for intramolecular addition of carboxylic acids to alkynes (hydro-oxycarbonylation), which afforded the corresponding 5- and 6-membered lactones in moderate...
作者:Cole A. Witham、Pablo Mauleón、Nathan D. Shapiro、Benjamin D. Sherry、F. Dean Toste
DOI:10.1021/ja071231+
日期:2007.5.1
A series of gold(I)-catalyzed oxidative rearrangement reactions of alkynes using sulfoxides as stoichiometric oxidants are reported. The reactions are postulated to proceed through intermolecular oxygen atom transfer from the sulfoxide to gold(I)−carbenoid intermediates. Under the conditions for gold(I)-catalyzed oxidative rearrangement, 1,6-enynes are isomerized to cyclopropyl aldehydes, homopropargyl