Transformation of indoline spiropyrans to bridged 1,3-benzoxazepino[3,2-a]indoles via carbanions stabilized by a cyano group

• Condensation of 1-cyanomethyl-2,3,3-trimethyl-3H-indolium perchlorate with ortho-hydroxy-substituted aromatic aldehydes afforded 1-cyanomethylindoline spiropyrans. The latter underwent rearrangement to bridged 1,3-benzoxazepino[3,2-a]indoles on treatment with a base. The mechanism of the rearrangement includes generation of a carbanion stabilized by a cyano Group.

Subject headings

NATURVETENSKAP  -- Kemi -- Organisk kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Organic Chemistry (hsv//eng)

Keyword

13-methano-1

3-benzoxazepino[3

5a

2-a]indoles. spiropyrans

carbanions

cyclization

Publication and Content Type

art (subject category)

ref (subject category)