Collect. Czech. Chem. Commun. 2007, 72, 1579-1590

Synthetic Utility of 1-Hydroxycarbazole-2-carbaldehydes - Syntheses of Furo-, Oxazino- and Pyranocarbazoles

Arputharaj E. Martin and Karnam J. Rajendra Prasad*

Department of Chemistry, Bharathiar University, Coimbatore 641 046, Tamil Nadu, India


Reaction of 1-hydroxycarbazole-2-carbaldehydes 1 with phenacyl bromide yielded 2-benzoyl-10H-furo[2,3-a]carbazoles 2, whereas the reaction with ethyl bromoacetate yielded 1-oxo-1,2-dihydro[1,4]oxazino[2,3,4-jk]carbazole-4-carbaldehyde (4). The reaction of 1 with ethyl acetoacetate and also with diethyl malonate yielded the pyranocarbazoles 6 and 7, respectively. All the products were characterized by spectral and analytical means. Plausible mechanisms of product formation are proposed.

Keywords: Carbazoles; Pyranes; Fused heterocycles; Aldehydes; Cyclizations; Furocarbazoles.

References: 18 live references.