147198-41-2Relevant articles and documents
Synthesis of 3-aryl-1-(4-methoxyphenyl)-2--2-propen-1-ones and benzopyran derivatives
Verma, Braham S.,Dhindsa, Kuldip Singh,Sangwan, Naresh K.
, p. 239 - 243 (2007/10/02)
Acylation of anisole (5) or m-methoxyphenol (6) with arylacetic acid (7 or 8) gives the corresponding deoxybenzoins (9-12) along with minor isomeric product 13 in one case.Acetylation of 4-hydroxy-4'-methoxydeoxybenzoin (10) with acetic anhydride in pyridine or its alkylation with N-(2-chloroethyl)diethylammonium/pyrrolidinium chloride furnishes the corresponding deoxybenzoin derivatives (14-16).Condensation of 9, 11, 15 and 16 with araldehydes affords the corresponding title compounds 2-propen-1-ones (17, 19 and 21-23). 1-(2-Hydroxy-4-methoxyphenyl)-2,3-diphenyl-2-propen-1-one (19) is isomerized using silica gel or hydrochloric acid to 2,3-trans-2,3-dihydro-7-methoxy-2,3-diphenyl-4H-1-benzopyran-4-one (24) which on sodium borohydride reduction provides a mixture of isomeric benzopyranols (25).Dehydration of 25 gives 7-methoxy-2,3-diphenyl-2H/4H-1-benzopyran (27).The isomeric 7-methoxy-2,4-diphenyl-2H/4H-1-benzopyran (28) is prepared by the reaction of 2,3-dihydro-7-methoxy-2-phenyl-4H-1-benzopyran-4-one (26) with phenylmagnesium bromide.Condensation of 11 with 7 in acetic anhydride/triethylamine furnishes 4-benzyl-7-methoxy-3-phenyl-2H-1-benzopyran-2-one (29).
