Chiral Copper Complexes of Phosphino Sulfenyl Ferrocenes as Efficient Catalysts for Enantioselective Formal Aza Diels−Alder Reactions of <i>N</i>-Sulfonyl Imines
作者:Olga García Mancheño、Ramón Gómez Arrayás、Juan C. Carretero
DOI:10.1021/ja038494y
日期:2004.1.1
catalytic amount of silver perchlorate, copper(I) bromide complexes of planar chiral 1-phosphino-2-sulfenylferrocenes behave as very efficient chiral Lewis acids catalysts in the formal Aza Diels-Alder reaction of N-arylsulfonyl aldimines with electron-rich dienes (Danishefsky's and related dienes). Mixing of equimolar amounts of the readily available enantiopure ferrocenyl P,S-bidentate ligand and CuBr quantitatively
A neworganocatalyticstrategy for the synthesis of enantioenriched aza‐Baylis–Hillman type products via a frustrated vinylogous reaction is presented. This process proceeds under mild conditions with good yields, completed Z/E selectivity and excellent enantioselectivities. Moreover, easy derivatizations of the final products led to important building blocks of organic synthesis such as 1,3‐aminoalcohols
Agent for lightening keratinic fibers, particularly human hair, wherein the agent contains, in a cosmetic carrier, at least one oxidizing agent chosen from hydrogen peroxide and/or a solid addition product thereof with organic or inorganic compounds, and at least one sulfonimine of formula (I)—
enantioselective Mannich-type reaction between glycinate Schiff base and imines has been one of the most efficient routes for accessing α,β-diamino acids. However, the glycinate Schiff bases used in the references were almost ketimines. Only several examples of aldimines were used in the presence of metal catalyst. We developed the first example of an asymmetric direct Mannich reaction using aldimines of glycinates
Mix and go: The quinidine amide 1 catalyzed [2+2] cycloaddition between N‐sulfonylimines 2 and alkyl 2,3‐butadienoates 3 afforded the R‐configured azetidines 4 in excellent yields and enantioselectivities (M.S.=molecular sieve). The S enantiomer was obtained when a quinine amide catalyst, the pseudoenantiomer of 1, was used.