Synfacts 2009(4): 0368-0368  
DOI: 10.1055/s-0028-1087890
Synthesis of Heterocycles
© Georg Thieme Verlag Stuttgart ˙ New York

Lithiated Dithiane Ring Opening of N-Protected Aziridines

Contributor(s): Victor Snieckus, Johnathan Board
K. Sakakibara, K. Nozaki*
The University of Tokyo, Japan
Further Information

Publication History

Publication Date:
23 March 2009 (online)

Significance

Reported is the ring opening of aziridines with lithiated 1,3-dithiane and its derivatives to afford 1,3-dithiane-protected β-amino ­carbonyl products. In the case of 1,3-dithiane-2-carboxylic acid, the products proved too polar to isolate and therefore were cyclized to give 3-protected pyrrolidine-2,3-diones. Enantiopurity was retained where aziridines with a defined stereocenter were used. One example of removal of each protecting group was shown. In the case of the N-Bus product, the 1,3-dithiane required removal prior to deprotection due to its instability ­towards triflic acid. The N-SES product was converted into the corresponding N-carbamate as it is known that N-acylation facilitates SES removal.