Wu, Huaimo; Liu, Song; Wang, Youyi; Yuan, Man; Zhang, Hong; Zhou, Hua; Xiao, Lianbo; Zheng, Changwu; Xu, Hongxi published an article in 2021, the title of the article was An efficient approach for the synthesis of 1,2-dihydroxanthones enabled by one-pot Claisen condensation/cyclization reactions.Synthetic Route of 118-55-8 And the article contains the following content:
In this report, a mild, efficient and green method for the synthesis of 1,2-dihydroxanthones (DHXs) I (R = H, Me, 3-methylbut-2-en-1-yl; R1 = H, Me; R2 = Me, Ph, 2,2,2-trifluoroethyl, but-3-en-1-yl, etc.; R3 = H, Me; R4 = H, F, OMe, Cl, Br, I; R5 = H, Me, OMe, Cl, CF3, F; R4R5 = -CH:CHCH:CH-; R6 = H, Cl, Me, prop-2-en-1-yl) and II (R7 = H, OMe) has been developed in one pot through Claisen condensation and O-cyclization under waste-induced relay catalysis with min. organic solvents. The byproduct (HMDS or NH3·H2O) of the first step turned out to be the promoter for the second step, which could efficiently proceed in aqueous media without the addition of other catalysts. The reactions using trifluoroethyl salicylates 2-OH-3-R6-4-R5-5-R4-6-R3C6HC(O)OCH2CF3 could be performed under mild conditions to ensure the generation of vulnerable DHXs I and II in high yields. The substrate scope is very broad regardless of the substituent type and its position on the structure. Specifically, the versatility of DHXs I (R = R1 = R3 = R4 = R5 = R6 = H; R2 = Me) was demonstrated by their conversion to xanthones I (R = 3-methylbut-2-en-1-yl; R1 = R3 = R4 = R5 = R6 = H; R2 = Me)/II (R7 = H) and other complex structures III/IV. The experimental process involved the reaction of Phenyl Salicylate(cas: 118-55-8).Synthetic Route of 118-55-8
The Article related to dihydroxanthone preparation green chem, cyclohexenone salicylate claisen condensation heterocyclization, Heterocyclic Compounds (One Hetero Atom): Benzopyrans (Including Coumarins, Isocoumarins, Chromones, Benzopyrones, Dibenzopyrans, and Other Arenopyrans) and other aspects.Synthetic Route of 118-55-8
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