AgAsF6 as safe alternative to AgClO4 for generating cationic zirconocene species: Utilities in lewis acid-promoted selective CC bond forming reactions
synthesis, AgAsF6 proved to be an efficient catalyst that serves as a safe alternative to AgClO4. Scope and limitation is discussed on this new catalyst in the processes including (1) alkyl/alkenyl transfer reaction from organozirconocene chloride to aldehyde, (2) two- and four-carbon homologation of aldehyde, (3) dual synthetic methods of 1,3-dienes from aldehydes/ketones via 1,3-bimetallic species
Photochemical reaction of ortho-formylbenzyltrialkylstannanes for the generation of α-oxy-o-quinodimethane
作者:Hiroshi Sano、Daisuke Asanuma、Masanori Kosugi
DOI:10.1039/a904872c
日期:——
Irradiation of o-formylbenzyltrialkylstannanes in benzene gives α-trialkylstannoxy-o-quinodimethanes which are trapped with dienophiles at room temperature to afford cycloadducts with high stereoselectivities, while the corresponding silane and germane gave a different type of o-quinodimethane and moderate stereoselectivities in cycloadditions.
o-Tributylstannylmethyl benzaldehyde reacts with Zn in the presence of TMSCl and 2,6-lutidine at room temperature to give alpha-trimethylsiloxy-o-quinodimethane, which is trapped with dienophiles to afford cycloadducts in good to high yields, Copyright (C) 1996 Elsevier Science Ltd.
Soon Hyung Woo, Tetrahedron Lett, 35 (1994) N 23, S 3975-3978
作者:Soon Hyung Woo
DOI:——
日期:——
Proline-catalyzed asymmetric Diels–Alder reactions of an o-quinodimethane
作者:Hidenori Shirakawa、Hiroshi Sano
DOI:10.1016/j.tetlet.2014.05.107
日期:2014.7
Catalytic asymmetricDiels–Alderreaction of α-amino-o-quinodimethane with α,β-unsaturated aldehydes was achieved with high diastereo- and enantioselectivities in the presence of l-proline, which acts as a promoter to generate the quinodimethane from the corresponding precursor as well as a chiral catalyst for the enantioselective Diels–Alderreaction.