Premium
Size‐Induced Inversion of Selectivity in the Acylation of 1,2‐Diols
Author(s) -
Mayr Stefanie,
Zipse Hendrik
Publication year - 2021
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.202101905
Subject(s) - acylation , chemistry , reagent , steric effects , selectivity , aryl , diol , kinetics , organic chemistry , medicinal chemistry , catalysis , alkyl , physics , quantum mechanics
Relative rates for the Lewis base‐catalyzed acylation of aryl‐substituted 1,2‐diols with anhydrides differing in size have been determined by turnover‐limited competition experiments and absolute kinetics measurements. Depending on the structure of the anhydride reagent, the secondary hydroxyl group of the 1,2‐diol reacts faster than the primary one. This preference towards the secondary hydroxyl group is boosted in the second acylation step from the monoesters to the diester through size and additional steric effects. In absolute terms the first acylation step is found to be up to 35 times faster than the second one for the primary alcohols due to neighboring group effects.