Catalytic Asymmetric Carbene Transfer Reactions of Diazo Oxime Ethers with Olefins and Their Synthetic Applications
作者:Linh Da Ho、Nansalmaa Otog、Ikuhide Fujisawa、Seiji Iwasa
DOI:10.1021/acs.orglett.9b02771
日期:2019.9.20
The first catalytic asymmetric cyclopropanation of diazo oxime ethers with olefins was developed. In the presence of a Ru(II)-Pheox catalyst, various optically active cyclopropyl oxime derivatives were obtained in high yields (up to 99%) with high enantioselectivities (up to 98% ee). Furthermore, optically active cyclopropyl oxime ethers could be successfully converted into the corresponding cyclopropyl
Asymmetric reduction of oxime ethers. Distinction of anti and syn isomers leading to enantiomeric amines.
作者:Yoji Sakito、Yukio Yoneyoshi、Gohfu Suzukamo
DOI:10.1016/s0040-4039(00)80059-3
日期:1988.1
Anti and syn ketoxime ethers were reduced with a chiral reducing agent prepared from (−)-norephedrine and 2 eq of BH3 to give S and R amines respectively in up to 92% ee. The preferred absolute configuration of the amine was depended on the geometry of the oxime ether.
9,10-Dicyanoanthracene(DCA)-sensitized isomerization of (E)- and (Z)-isomers of an oxime ether of 2-acetylnaphthalene (E-1 and Z-1, respectively) was investigated in benzene by means of steady irradiation and laser flash photolysis. The excited singlet DCA was effectively quenched by E-1 and Z-1 to afford exciplexes, decay of which gave DCA triplets or 1 triplets. The triplet state of 1 was proposed