Synthesis of polyfunctional aliphatic carbonyl compounds under phase-transfer conditions

Diastereoselective Synthesis of and Mechanistic Understanding for the Formation of 2‐Piperidinones from Imines and Cyano‐Substituted Anhydrides

“…Synthesis of the anhydride was realized by the enolate alkylation of ethyl cyanoacetate with ethyl bromopropionate. [8] While this reaction quickly forms the double alkylation product, we were able to synthesize multigram quantities of the desired diester.H ydrolysis of the diester with lithium hydroxidef ollowed by dehydration with trifluoroacetic anhydride (TFAA) provided the anhydride on multigram scale [Eq.…”

Chemoenzymatic Stereoselective Synthesis of Substituted γ‐ or δ‐lactams with Two Chiral Centers via Transaminase‐catalysed Dynamic Kinetic Resolution

“…The keto esters 19 a (diethyl 2-acetylsuccinate) and 19 c (diethyl 2-acetylhexanedioate) in Table 1 were prepared through CÀ C bond formation of ethyl 3-oxobutanoate and ethyl 2-bromoacetate or ethyl 4-bromobutanoate in alkaline media. [24] Keto ester 19 b (diethyl 2-acetylpentanedioate) was synthesized from ethyl 3-oxobutanoate and ethyl acrylate in absolute THF with DBU as the catalyst. [25] Keto ester 19 d (ethyl 3-cyano-4-oxopent-2enoate) was obtained through condensation of 3-oxobutanenitrile with ethyl glyoxalate followed by Pd/C-catalysed hydrogenation.…”

Syntiesis of annelated 1,2,3‐thiadiazole derivatives

“…Alkylation of methyl cyanoacetate with methyl chloroacetate under phase-transfer conditions is known from the literature, but due to double alkylation the yield of the desired monoalkylation product is just 25% [18]. Dimethyl cyanosuccinate is also available starting from aspartic acid via reaction of 2-chlorosuccinate with sodium cyanide [19].…”