Catalytic Enantioselective Desymmetrization of Norbornenoquinones via C(sp<sup>2</sup>)–H Alkylation
作者:Rahul Sarkar、Santanu Mukherjee
DOI:10.1021/acs.orglett.6b03168
日期:2016.12.2
The enantioselective Diels–Alder (DA) reaction with monosubstituted p-benzoquinones is an unmet challenge. A new approach for the enantioselective synthesis of monosubstituted quinone-DA adducts is presented based on C(sp2)–H alkylative desymmetrization of meso-DA adducts. Catalyzed by a tertiary amino-thiourea derivative, this reaction utilizes nitroalkanes as the alkylating agents and generates densely
A desymmetrization approach to centrally chiral unfunctionalized arenes is developed through the enantioselective de novo construction of the arene ring by oxidative [4+2]-cycloaddition of polycyclic meso-cyclohexenediones. Catalyzed by a diphenylprolinol silyl ether, this external oxidant-free protocol gives rise to diversely substituted chiral arenes with outstanding enantioselectivity (up to >99
Synthesis, characterization and crystal density modeling of spiropolycyclic oxiranes
作者:Alan P Marchand、Rajesh Shukla、Paul R.J Davey、Herman L Ammon、Zuyue Du、Simon G Bott
DOI:10.1016/s0040-4020(98)00165-3
日期:1998.4
and bis-epoxides 1–6 have been synthesized. The structures of 1–6 have been established unequivocally via application of single crystal X-ray crystallographic methods. The crystaldensities of 1–6 (from X-ray crystallographic data) are compared with the results of density predictions.
Singh, Vishwakarma; Raju, Bhupathiraju N. S., Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 1996, vol. 35, # 4, p. 303 - 311