A Cascade Approach to Cyclic Aminonitrones: Reaction Discovery, Mechanism, and Scope
摘要:
Treatment of omega-epoxynitriles with hydroxylamine affords cyclic aminonitrones in a single step and with high stereoselectivity. The scope of this novel transformation was explored in a series of examples. The aminonitrone products were shown to be useful substrates for further selective elaboration.
A Cascade Approach to Cyclic Aminonitrones: Reaction Discovery, Mechanism, and Scope
摘要:
Treatment of omega-epoxynitriles with hydroxylamine affords cyclic aminonitrones in a single step and with high stereoselectivity. The scope of this novel transformation was explored in a series of examples. The aminonitrone products were shown to be useful substrates for further selective elaboration.
and -stannane, the photosubstitution occurred at both α- and γ-positions of the allylic moiety in a constant ratio, regardless of the kinds of metals. 1,3-Dicyanobenzene (m-DCB) was less reactive to the photosubstitutionreaction. The reactivity of group 14 organometallic compounds increased in the order: Si- < Ge- < Sn-compounds. The photoreactions were sensitized by aromatic hydrocarbons such as
Photosubstitution of Dicyanobenzenes by Group 14 Organometallic Compounds via Photoinduced Electron-Transfer. Additive and Medium Effects on Photoinduced Electron Transfer Reaction
The phenanthrene-sensitized photoreaction of 1,2- and 1,4-dicyanobenzenes with group14organometallic compounds containing allylic and benzylic groups in CH3CN afforded the corresponding 2- and 4-allylated and -benzylated benzonitriles in high yields. These photoreactions were accelerated by the addition of Mg(CLO4)2 and benzene derivatives.
Asymmetric Intramolecular Arylcyanation of Unactivated Olefins via C−CN Bond Activation
作者:Mary P. Watson、Eric N. Jacobsen
DOI:10.1021/ja805094j
日期:2008.9.24
The enantioselective, intramolecular arylcyanation of unactivated olefins via C-CN bondactivation has been accomplished using a Ni(0) catalyst and BPh3 co-catalyst. High enantioselectivities are achieved using TangPHOS as a chiral ligand. This method allows the generation of two new C-C bonds and one new quaternary carbon stereogenic center in a single synthetic step, converting readily available