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Synthesis of Chiral, Enantiopure Allylic Amines by the Julia Olefination of ?-Amino Esters.

ABSTRACT: The four-step conversion of a series of N-Boc-protected l-amino acid methyl esters into enantiopure N-Boc allylamines by a modified Julia olefination is described. Key steps include the reaction of a lithiated phenylalkylsulfone with amino esters, giving chiral ?-ketosulfones, and the reductive elimination of related ?-acetoxysulfones. The overall transformation takes place under mild conditions, with good yields, and without loss of stereochemical integrity, being in this respect superior to the conventional Julia reaction of ?-amino aldehydes.

SUBMITTER: Benedetti F

PROVIDER: S-EPMC6273449 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Synthesis of Chiral, Enantiopure Allylic Amines by the Julia Olefination of α-Amino Esters.

Benedetti Fabio F Berti Federico F Fanfoni Lidia L Garbo Michele M Regini Giorgia G Felluga Fulvia F

Molecules (Basel, Switzerland) 20160621 6

The four-step conversion of a series of N-Boc-protected l-amino acid methyl esters into enantiopure N-Boc allylamines by a modified Julia olefination is described. Key steps include the reaction of a lithiated phenylalkylsulfone with amino esters, giving chiral β-ketosulfones, and the reductive elimination of related α-acetoxysulfones. The overall transformation takes place under mild conditions, with good yields, and without loss of stereochemical integrity, being in this respect superior to th ...[more]

PMID: 27338326

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