作者:Mónica Alvarez-Pérez、Stephen M. Goldup、David A. Leigh、Alexandra M. Z. Slawin
DOI:10.1021/ja7102394
日期:2008.2.1
A chemically driven molecular information ratchet is described. The equilibrium macrocycle distribution in a [2]rotaxane is driven away from its 50:50 population of thread binding sites to a 33:67 ratio by benzoylation under the influence of a chiral catalyst The reaction corresponds to a dynamic kinetic resolution of rotaxane co-conformers that interconvert through shuttling.
A Three-Compartment Chemically-Driven Molecular Information Ratchet
作者:Armando Carlone、Stephen M. Goldup、Nathalie Lebrasseur、David A. Leigh、Adam Wilson
DOI:10.1021/ja302711z
日期:2012.5.23
We describe a three-compartment rotaxane information ratchet in which the macrocycle can be directionally transported in either direction along an achiral (disregarding isotopic labeling) track. Chiral DMAP-based catalysts promote a benzoylation reaction that ratchets the displacement of the macrocycle, transporting it predominantly to a particular end compartment determined by the handedness of the catalyst.
Intramolecular Base-Free Catalytic Wittig Reaction: Synthesis of Benzoxepinones
作者:Aiga Grandane、Lars Longwitz、Catrin Roolf、Anke Spannenberg、Hugo Murua Escobar、Christian Junghanss、Edgars Suna、Thomas Werner
DOI:10.1021/acs.joc.8b02789
日期:2019.2.1
A straightforward two-step synthesis of benzoxepinones was developed via base-free phosphane-catalyzed Wittigreaction. 3-Methyl-1-phenyl-2-phospholene 1-oxide was used as a precatalyst and trimethoxysilane as a reducing agent. Additionally benzoic acid is employed as a catalyst to facilitate the reduction of the phosphane oxide. Mechanistic investigation revealed the formation of a coumarin as a side