Chemoselective and direct functionalization of methyl benzyl ethers and unsymmetrical dibenzyl ethers by using iron trichloride.
Methyl and benzyl ethers are widely utilized as protected alcohols due to their chemical stability, such as the low reactivity of the methoxy and benzyloxy groups as leaving groups under nucleophilic conditions. We have established the direct azidation of chemically stable methyl and benzyl ethers derived from secondary and tertiary benzyl alcohols. The present azidation chemoselectively proceeds at the secondary or tertiary benzylic positions of methyl benzyl ethers or unsymmetrical dibenzyl ethers and is also applicable to direct allylation, alkynylation, and cyanation reactions, as well as the azidation. The present methodologies provide not only a novel chemoselectivity but also the advantage of shortened synthetic steps, due to the direct process without the deprotection of the methyl and benzyl ethers.
Laboratory of Organic Chemistry, Gifu Pharmaceutical University, 1-25-4 Daigakunishi, Gifu 501-1196 (Japan). sawama@gifu-pu.ac.jp.
Yoshinari
Y
Sawama
Ryota
R
Goto
Saori
S
Nagata
Yuko
Y
Shishido
Yasunari
Y
Monguchi
Hironao
H
Sajiki
D001592:Benzyl Alcohols / Q000737:chemistry*; D001593:Benzyl Compounds; D002384:Catalysis; D002712:Chlorides / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry*; D008738:Methyl Ethers / Q000737:chemistry*; D015394:Molecular Structure; D010647:Phenyl Ethers / Q000737:chemistry*
D001592:Benzyl Alcohols; D001593:Benzyl Compounds; D002712:Chlorides; D005290:Ferric Compounds; D008738:Methyl Ethers; D010647:Phenyl Ethers; C076624:dibenzyl ether; C024555:ferric chloride
azides; chemoselectivity; ethers; functionalization; iron