Kinetic and mechanistic studies of NEt3-catalyzed intramolecular aminolysis of carbamate.
The mechanism of the NEt 3-catalyzed intramolecular aminolysis of Z- 1 in acetonitrile or aqueous acetonitrile solutions is suggested to involve rate-determining collapse of T (+/-) through simultaneous H-abstraction and ethoxide expulsion of E2 process. The evidence for that includes the primary isotope effect of k H/ k D = 1.66 in acetonitrile, general-base catalysis in aqueous buffer solutions, salt effect, and the proposed water-stabilized rate-determining transition states (TS1 and TS2) in the water-titration experiments.
Sung
Kuangsen
K
Department of Chemistry, National Cheng Kung University, Tainan, Taiwan. kssung@mail.ncku.edu.tw
Zhuang
Bo-Ren
BR
Huang
Pin-Mei
PM
Jhong
Sheng-Wei
SW
D000588:Amines / Q000737:chemistry*; D002219:Carbamates / Q000737:chemistry*; D002384:Catalysis; D007700:Kinetics; D013056:Spectrophotometry, Ultraviolet
D000588:Amines; D002219:Carbamates