Catalytic Asymmetric Direct Vinylogous Michael Addition of Deconjugated Butenolides to Maleimides for the Construction of Quaternary Stereogenic Centers
作者:Madhu Sudan Manna、Santanu Mukherjee
DOI:10.1002/chem.201203180
日期:2012.11.26
Competition under control: A practical and efficient directasymmetricvinylogousMichael reaction of deconjugatedbutenolides has been developed (see scheme). The products of this reaction, highly functionalized chiral succinimides, are obtained in excellent yield with high diastereoselectivity (up to d.r.=18:1) and outstanding enantioselectivity (up to e.r.=99.5:0.5).
Heterocyclization reactions between derivatives of 5-aminopyrazoles and N-arylmaleimides were studied and it was established that several directions are possible. Cyclizations involving 1,3-unsubstituted 5-aminopyrazoles yielded mixtures of two regioisomeric compounds, pyrazolo[1,5-a]pyrimidine-7-carboxamides and pyrazolo[3,4-b]pyridine-4-carboxamides. Reactions of 4-substituted 5-aminopyrazoles in boiling acetic acid or N,N-dimethylformamide in most cases gave pyrazolo[1,5-a]pyrimidine-7-carboxamides as the sole product. The treatment of 1-substituted 5-aminopyrazoles with maleimides possesses high selectivity only in N,N-dimethylformamide yielding pyrazolopyridines while in acetic acid the formation mixtures with pyrrolopyrazolones is observed. The key intermediates of the reaction studied were isolated and discussed.
COMPOSITIONS COMPRISING A REACTIVE MONOMER AND USES THEREOF
申请人:Hood David K.
公开号:US20130025495A1
公开(公告)日:2013-01-31
Disclosed herein are compositions such as ink or coating compositions that include at least one reactive monomer that includes a maleimide of the general formula (I) A- is or includes an aryl, an alkylaryl, or an arylalkyl. The reactive monomer may be or include 4-butylphenyl maleimide. The composition may also include a reactive co-solvent that may include at least one of a (meth)acryl monomer or prepolymer, a (meth)acryl ester of an epoxy type monomer or prepolymer, and a urethane type monomer or prepolymer.