- Synthesis of dihydrobenzo[h]coumarins and their 4-methyl analogs
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Dihydrobenzo[h]coumarins (5a-7a) and their 4-methyl analogs (5b-7b) were synthesized from 1-naphthol via two different synthetic routes. One pathway is the direct condensation of 5,8-dihydro-1-naphthol (9) with malic acid or ethyl acetoacetate, affording 7,10-dihydrobenzo[h]coumarins 7a and 7b, respectively. The other is through the oxidation of 7,8,9,10-tetrahydrobenzo[h] coumarins (15a-b), followed by the reduction of the carbonyl group and dehydration of hydroxyl group, giving 7,8-dihydrobenzo[h]coumarins (5a, b) and 9,10-dihydrobenzo[h]coumarins (6a, b). The regio selectivities for the oxidation reactions of 15a, b were rationalized on the basis of quantum chemical calculations and further confirmed by the X-ray crystallographic analysis of the derivatives of oxidation products. Copyright Taylor & Francis, Inc.
- Wang, Yang,Huang, Shaoxu,Xia, Peng
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- NOVEL AND FACILE REDUCTION OF PHENOL DERIVATIVES WITH SAMARIUM DIIODIDE-BASE SYSTEM
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Phenol was rapidly reduced with samarium diiodide-base system in the presence of protic solvent at room temperature to afford 3-cyclohexen-1-ol accompanied by cyclohexanol.The similar reduction of 4-methoxyphenol and 2-naphthol gave 4-hydroxycyclohexanone and 1,2,3,4-tetrahydro-2-naphthol in excellent yield, respectively.
- Kamochi, Yasuko,Kudo, Tadahiro
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p. 4169 - 4172
(2007/10/02)
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