ISSN:
0009-2940
Keywords:
Carbene complexes
;
Chromium complexes
;
Benzannulation
;
Cyclopentannulation
;
Benzocarbazoles
;
Indenoindoles
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
2-Alkynylanilinocarbene chromium complexes 1-7 bearing a rigid arene C2 spacer between the aminocarbene and alkyne units were prepared from pentacarbonyl(aroyl)chromates(-I), acetyl bromide, and 2-alkynylanilines. They undergo intramolecular cyclization the course of which depends on the substitution pattern at the alkyne terminus. A tandem alkyne insertion into the metal-carbene bond/carbonylation sequence affords Cr(CO)3-coordinated 3-indolylketenes 8, 9, 12-14 by using a bulky substituent; the rate of the reaction increases with N-alkylation. Less bulky n-alkynylanilinocarbene complexes 4, 5 exhibit two competing carbene annulation sequences: Benzannulation leads to benzo[a]carbazoles 15, 16, whereas cyclopentannulation without prior carbonylation furnishes indeno[1,2-b]indoles 17, 18.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19961290606
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