Journal of Organic Chemistry p. 2317 - 2324 (1990)
Update date:2022-07-30
Topics:
Capon, Brian
Wu, Zhen-Ping
N-Phenylcyclohex-1-en-1-amine, N-(p-chlorophenyl)cyclohex-1-en-1-amine, the N-aryl-2-methylprop-1-en-1-amines, Me2C=CHNLC6H4X, L = H, D, X = H, p-Cl, p-Me, p-MeO, m-NO2, the N-alkyl-2-methylprop-1-en-1-amines, Me2C = CHNDR, R = Me, Et and the (E)-N-alkylprop-1-en-1-amines, MeHC = CHNDR, R = Me, t-Bu, were generated in solution from their N-trimethylsilyl derivatives and characterized by NMR spectroscopy.N-(p-Nitrophenyl)-2-methylprop-1-en-1-amine was isolated from the reaction of isobutyraldehyde and p-nitroaniline, and appreciable amounts (>10percent) of the N-arylcyclohex-1-en-1-amines and N-aryl-2-methylcyclohex-1-en-1-amines were found to be present at equilibrium in DMSO-d6 solution when the aryl group was phenyl, p-chlorophenyl, m-nitrophenyl, or p-nitrophenyl.The kinetics of hydrolysis of all the N-aryl secondary enamines obtained in the above ways were measured in aqueous solution and compared with those of the corresponding N-methyl tertiary enamines.With all enamines there was a region of pH in which kobsd was proportional to 10-pH, and under such conditions it was considered that the rate-determining step was C-protonation.This was supported by the isotope effect kH(1+)/kD(1+) = ca. 3, the observation of general acid catalysis, the much faster rate of hydrolysis of the corresponding imines, and the negative ρ- values.It was found that in the cyclohexenyl series the secondary and tertiary enamines were hydrolyzed at similar rates when the substituents in the aryl group were the same, but in the 2-methylcyclohexenyl and 2-methylpropenyl series the secondary enamines were hydrolyzed much faster than the corresponding tertiary enamines.This was attributed to the tertiary enamines being hindered from attaining the most favorable conformation for p-? conjugation.
View MoreXi'an yuanfar international trade company
website:https://www.yuanfarchemical.com
Contact:86-029-88745613 ext 828
Address:Floor19th ,B Building, Oak Block,No.36 South Fenghui Road, Dev. Zone of High-Tech Ind.,Xi’an, China
TAIZHOU XINGCHENG CHEMPHARM CO.,LTD.
Contact:0086-0576-88551200,88886292 ,88880039
Address:B Area. 10 Floor.Yaodadasha. 289#.Shifu Road.Taizhou.Zhejiang.China
Zhengzhou Minzhong Pharmaceutical Co.,ltd
Contact:0086-371-65797115
Address:15/F,Jiangshan Bldg, NO.126 Huanghe Road,Zhengzhou, China
SHANDONG AONA CHEMICAL CO.,LTD.
Contact:86-532-85762926
Address:LIUYUAN TOWN, ZAOZHUANG CITY, SHANGDONG PROVINCE.
TAIZHOU XINGCHENG CHEMPHARM CO.,LTD.
Contact:0086-0576-88551200,88886292 ,88880039
Address:B Area. 10 Floor.Yaodadasha. 289#.Shifu Road.Taizhou.Zhejiang.China
Doi:10.1155/2010/230707
(2010)Doi:10.1021/jm3008568
(2012)Doi:10.1246/bcsj.62.2701
(1989)Doi:10.1021/ol102468k
(2010)Doi:10.1080/00397911.2010.541964
(2012)Doi:10.3762/bjoc.6.119
(2010)