Synthesis and applications of a highly fluorous alkoxy ethyl ether protective group

A readily recyclable, fluorous alkoxy ethyl ether protecting group has been developed that allows for simple purification of small to medium-sized org anic molecules by liquid-liquid extraction with FC-72/organic/aqueous solve nts. The precursor vinyl ether 3 can be prepared in large quantity in a str aightforward two step reaction sequence, Primary, secondary, and tertiary a lcohols are protected in good to excellent yields, and the fluorous label i s removed by mild acid treatment. The N-protection of 2-fluoroaniline demon strates the feasibility of using 3 with amines. (C) 1999 Elsevier Science L td. All rights reserved.