Neber-type cyclizations

These intermediates with benzyhnagnesinm bromides gave 2-benzyl-2/7-azirines 8 in 50-80% yields, bnt potassinm phthahmide and sodium salt of benzenethiol converted them into the corresponding azirines 9 and 10 in good yields (equation 4). Similar Neber-type cyclization of a-hthio oxime ethers to highly reactive azirines was recently reported. ... 

Taber and Tian have employed the Neber protocol to prepare a-aryl azirines that underwent thermal rearrangement to afford substituted indoles via a unique Ie type ring closure <06JACS1058>. A variety of substituted N-alkyl and N-aryl indoles have been prepared by Zhao and co-workers who observed Ie cyclization of 2-aryl-3-arylamino-2-... 

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