207679-10-5Relevant academic research and scientific papers
Stereoselective synthesis of axially chiral natural products, (-)- steganone and O,O'-dimethylkorupensamine A, utilizing planar chiral (arene)chromium complexes
Kamikawa, Ken,Watanabe, Takashi,Daimon, Akira,Ue Mura, Motokazu
, p. 2325 - 2337 (2000)
Palladium(0)-mediated Suzuki-Miyaura cross-coupling of planar chiral (2,6-disubstituted bromobenzene)chromium complexes with o-substituted arylboronic acids in the presence of sodium carbonate under refluxing in aqueous methanol gave stereoselectively axially chiral mono Cr(CO)3- complexed biaryls. The axial stereochemistry of the cross-coupling products was found to be largely dependent on the steric bulkiness of ortho substituent of arylboronic acids and reaction conditions. The cross-coupling with o-alkyl or hydroxymethyl substituted arylboronic acids gave kinetically controlled products in which the ortho substituents were oriented in syn- configuration to the tricarbonylchromium fragment. On the other hand, o- formyl phenylboronic acid produced thermodynamically stable anti-coupling products under the same conditions. By utilizing these methodologies, biologically active axially chiral natural products, (-)-steganone and O,O'- dimethyl derivative of the natural product of korupensamine A, were stereoselectively synthesized. (C) 2000 Elsevier Science Ltd.
Stereoselective synthesis of O,O-dimethylkorupensamine A via palladium(o)-mediated cross-coupling of a planar chiral (arene)Cr(CO)3 complex with naphthylboronic acid
Watanabe, Takashi,Uemura, Motokazu
, p. 871 - 872 (1998)
O,O-Dimethylkorupensamine A was stereoselectively synthesized by using the palladium(o)-mediated cross-coupling of the enantiomerically pure tricarbonylchromium complex of 3,5-dimethoxy-2-bromobenzene having a functional group at C-l position with naphthy
