Regioselective Synthesis of Polyheterocycles From 4-Cyclohex-2-ENYL-3-Hydroxy-1-Methylquinolin-2(1H)-One |
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Authors: | K C Majumdar A K Kundu |
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Institution: | Department of Chemistry , University of Kalyani , Kalyani, 741 235, W.B, INDIA |
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Abstract: | 4-Cyclohex-2-enyl-3-hydroxy-1-methylquinolin-2(1H)-one (4) was prepared in 90% yield by the thermal 3,3]sigmatropic rearrangement of 3-cyclohex-2-enyloxy-1-methylquinolin-2(1H)-one (3) in refluxing chloroben-zene for 10 h. Compound (4) was cyclised through a sequence of reactions viz. i) acetylation ii) addition of bromine and iii) treatment of the acetyl dibromo compound (6) with base to give a bicyclic product (7) in 90% yield. Treatment of compound 4 with pyridine hydro-bromide perbromide in dichloromethane at 0–5° C afforded a cyclic product 8 in excellent yield. Compound 4 when treated with cold conc. sulphuric acid at 0–5° C furnished the bicyclic product 12 in 89% yield. |
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Keywords: | Indolines Sulfonic acids Sulfonyl chlorides Thiazoles |
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