1072798-29-8Relevant articles and documents
Organocatalytic methods for chemoselective O-tert-butoxycarbonylation of phenols and their regeneration from the O-t-Boc derivatives
Chankeshwara, Sunay V.,Chebolu, Rajesh,Chakraborti, Asit K.
supporting information; scheme or table, p. 8615 - 8618 (2009/04/11)
(Chemical Equation Presented) Carbon tetrabromide (CBr4) catalyzes O-tert-butoxycarbonylation of functionalized phenols without any side reactions (bromination, addition of CBr3 to a double bond, and formation of symmetrical diaryl carbonates, cyclic carbonates, or carbonic-carbonic anhydrides). The parent phenols are regenerated from the O-t-Boc derivatives by the catalyst system CBr4-PPh3 without affecting other protecting groups (aryl alkyl ether, alkyl ester, and thioacetal) or competitive side reaction such as bromination, nitrene (from NO2) and α,α-dibromoolefine (with CHO/COMe) formation, and transesterification (with CO2Me/Et) taking place.