A study of the Claisen rearrangement of 7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one derivatives
摘要:
The Claisen rearrangement of 7-(3-phenyl-2-propenyloxy)-3-phenyl-(4 H)-1-benzopyran-4-one (2a) gave 7-hydroxy-8-(1-phenyl-2-propenyl)-3-phenyl-(4H)-1-benzopyran-4-one(3a) and 2,3-dihydro-2,6-diphenyl-3-methyl-(7H)furo[2,3-h]-1-benzopyran-7-one (7a). 2-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4 H)-1-benzopyran-4-one (2 b) afforded 4 b and 7 b. 8-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4 H)-1-benzopyran-4-one (12) gave only the alkali soluble product 7-hydroxy-8-methyl-6-(1-phenyl-2-propenyl)-3-phenyl-(4 H)-1-benzopyran-4-one (13). 3 a, 4 b, and 13 were further cyclized in acidic medium to 9 a, 10 b, and 14 followed by dehydrogenation.
A study of the Claisen rearrangement of 7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one derivatives
摘要:
The Claisen rearrangement of 7-(3-phenyl-2-propenyloxy)-3-phenyl-(4 H)-1-benzopyran-4-one (2a) gave 7-hydroxy-8-(1-phenyl-2-propenyl)-3-phenyl-(4H)-1-benzopyran-4-one(3a) and 2,3-dihydro-2,6-diphenyl-3-methyl-(7H)furo[2,3-h]-1-benzopyran-7-one (7a). 2-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4 H)-1-benzopyran-4-one (2 b) afforded 4 b and 7 b. 8-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4 H)-1-benzopyran-4-one (12) gave only the alkali soluble product 7-hydroxy-8-methyl-6-(1-phenyl-2-propenyl)-3-phenyl-(4 H)-1-benzopyran-4-one (13). 3 a, 4 b, and 13 were further cyclized in acidic medium to 9 a, 10 b, and 14 followed by dehydrogenation.