no-unwanted products, neutral reaction conditions and appropriateness for large-scale synthesis. Mechanism studies reveal that the in situ generated β-amino ketonefrom 3-chloropropiophenone and an ammonium salt undergoes C=N bond formation with a ketone followed by an intramolecular cyclization process (C=C bond), which are the decisive steps for pyridine synthesis.
Organocatalyzed Double C(sp<sup>3</sup>)−H Alkylation of Cyclic <i>N</i>‐Sulfonyl Ketimines with 3‐Chloropropiophenones: Selective Access to 2,3,6‐Trisubstituted Pyridines
作者:Ashvani Kumar Patel、Sampak Samanta
DOI:10.1002/ejoc.202300631
日期:2023.9
Efficient de novo access to 2,3,6-trisubstituted pyridines was successfully synthesized through a mono- or dialkylation reaction between 4/3-alkyl-N-sulfonyl ketimines with 3-chloropropiophenones using DIPEA/NaHCO3 as a cheap cooperative basic system and subsequent aza-cyclization in the presence of NH4OAc under an air.
3-chloro-1-(4-iodophenyl)propan-1-ol, and 3-chloro-1-phenylpropan-1-ol is described. The procedure is based on the enantiomer-selective acylation of the racemic alcohols in presence of lipase from Pseudomonasfluorescens (LAK) followed by the lipase from Candida rugosa (CRL) mediated hydrolysis of previously obtained enantiomerically enriched 1-aryl-3-chloropropyl esters. For the production of enantiopure (S)-1-ar