1998 phenol ethers

phenol ethersQ 0270

37 - 096Chemoselective O-Methylation of Phenols under Nonaqueous Condi-tion. — A highly selective O-alkylation of various phenols (I) (24 examples)is achieved using 0.5 equivalents of dialkylsulfate [cf. (II)] in dry THF in thepresence of LiOH as base. Use of other alkali or alkaline earth metal hydroxidesor carbonates gives only poor yields. Furthermore, tyrosines such as (IV) arecleanly methylated by this method without affecting other functional groupsor the optical purity. — (BASAK, A.; NAYAK, M. K.; CHAKRABORTI, A.K.; Tetrahedron Lett. 39 (1998) 27, 4883-4886; Dep. Chem., Univ. Burdwan,Burdwan 713 104, India; EN)

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