Ethyl N-(diphenylmethylene)glycinate as anionic glycine equivalent. Monoalkylation, dialkylation and Michael additions under solid-liquid phase-transfer catalysis
additions to ethylenic and acetylenic acceptors under appropriate solid-liquid phase transfer catalysis conditions. Further transformations of the α-disubstituted ketimines lead to α-alkylated aspartic and glutamic acid derivatives 10, 15, 19 and 26, to bicyclic amino acids or derivatives featuring pyrazolone and isoxazolone moieties 30 and 33, and to α-substituted (E)-3,4-dehydroglutamic acids.
Ethyl N-diphenylmethyleneglycinate reacts with one equivalent of alkylating agents in the presence of powdered potassium carbonate to afford, after hydrolysis, monoalkylated glycine esters. A similar process using two equivalents of alkylating agents in the presence of powdered potassium hydroxide and a phase transfer catalysts gives, after hydrolysis, dialkylated glycine esters.
Ring-closingmetathesis (RCM) with alpha,alpha-diallylglycyl peptides is shown to furnish alpha,alpha-cyclopentenylglycyl peptides as conformationally restrained analogues in the form of post-translational type peptide modification suitable for both peptidomimetic and combinatorial chemistry applications.
Enantioselective total synthesis of the highly selective sphingosine-1-receptor VPC01091 by the Heck desymmetrization of a non-activated cyclopentene-fused spiro-pyrrolidinone
A novel, efficient and enantioselective Heck–Matsuda desymmetrization of non-activated cyclopentene-fused spiro-pyrrolidinones was developed. The reaction provided the Heck products in good to excellent yields and selectivities and tolerated a variety of functional groups in arenediazonium tetrafluoroborates (12 examples) with respect to its electronics and substitution patterns. This methodology was
CHIRAL-SUBSTITUTED POLY-N-VINYLPYRROLIDINONES AND COMPLEXES WITH BIMETALLIC NANOCLUSTERS AND USES THEREOF IN ASYMMETRIC OXIDATION REACTIONS
申请人:Kansas State University Research Foundation
公开号:US20220204447A1
公开(公告)日:2022-06-30
Chiral polyvinylpyrrolidinone (CSPVP), complexes of CSPVP with a core species, such as a bimetallic nanocluster catalyst, and enantioselective oxidation reactions utilizing such complexes are disclosed. The catalytic complexes have exhibited the ability to achieve reaction products have a very high degree of optical purifies. These reaction products can be used as reagents in the synthesis of complex organic molecules, such as bioactive products, and C—H bond oxidation of complex molecules including various drugs and natural products.