Wada, Masanori published the artcileReactions of 1,8-Dimethoxy-9-phenylxanthen-9-ol in the Presence of an Acid, and Its Basicity, SDS of cas: 596-38-3, the publication is Bulletin of the Chemical Society of Japan (1999), 72(4), 779-785, database is CAplus.
In the presence of a catalytic amount of acid, the title xanthenol (1) reacted in acetone to give 1,8-dimethoxy-9-phenylxanthen-9-ylmethyl Me ketone. Analogous reactions were observed for Et Me ketone and acetophenone, but not for di-Et ketone. Propanal and butanal also reacted to give 2-(1,8-dimethoxy-9-phenylxanthen-9-yl)propanal and 2-(1,8-dimethoxy-9-phenylxanthen-9-yl)butanal, resp. In hot primary and secondary alcs.,1 was reduced to give 1,8-dimethoxy-9-phenylxanthene. 1 also reacted with methoxybenzenes, phenol, and N-alkylanilines to give 9-aryl-1,8-dimethoxy-9-phenylxanthenes. The basicity of 1, or the stability of the carbenium ion (pKR+ = -0.81), was measured in hydrochloric acid and compared with those of related 9-arylxanthen-9-ols, such as 1,8-dimethoxy-9-(2,6-dimethoxyphenyl)xanthen-9-ol (1.14), 9-(2,6-dimethoxyphenyl)xanthen-9-ol (4.80) (8), and 9-phenylxanthen-9-ol (0.75). The drastic differences in the reactivities and the basicity between 1 and 8 were attributed to a steric effect rather than an electronic effect.
Bulletin of the Chemical Society of Japan published new progress about 596-38-3. 596-38-3 belongs to alcohols-buliding-blocks, auxiliary class Other Aromatic Heterocyclic,Benzene,Alcohol, name is 9-Phenyl-9H-xanthen-9-ol, and the molecular formula is C4H6O3, SDS of cas: 596-38-3.
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