The chromous chloride promoted addition of N-chlorocarbamates to enol ethers the synthesis of N-alkoxycarbonyl derivatives of 2-amino sugars and of α-amino ketones and aldehydes

✍ Scribed by J. Lessard; H. Driguez; J.P. Vermes

• Book ID: 104229859
• Publisher: Elsevier Science
• Year: 1970
• Tongue: French
• Weight: 222 KB
• Volume: 11
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)99735-1

✦ Synopsis

In the preceding communication (l),we describe a new reaction which utilises chromous chloride to promote the addition of N-chlorocarbamates to olefins in good yjelds. We have applied this reaction to four enol ethers which illustrate the synthetic importance of the novel reaction.

Dihydropyran. -N-chlorourethane (NCU) (la) and dihydropyran (2) in a 1:2 molar ratio (CH3DH. -78OC, 30 min) gave the adducts 4a 3, 5a (m.p.62-63'0 and 6a (2) in 77X, 3% and 5% yields respectively (scheme I). Equilibration of either the tranS isomer 4a or the CiS isomer Ba with