Journal of Organic Chemistry p. 358 - 366 (1988)
Update date:2022-08-29
Topics:
Muneyuki, Ryonosuke
Yoshimura, Yohko
Tori, Kazuo
Terui, Yoshihiro
Shoolery, James N.
The additions and rearrangements of α-pinene (1) and apopinene (2) in deuteriated acids have been studied.The results obtained for 1 suggest that one of the reaction paths involves the tertiary cation intermediate 3a, but it has been difficult to define clearly the stereoelectronic relation between additions and rearangements in this system.However, in the case of deuterium addition to 2, the stereospecific deuterium location at C-6-endo in the product 7, the considerable preference for sterically hindered exo-side addition, and the rate enhancement of 48 times for CF3COOH addition to 2 compared with cyclohexane are interpreted to mean that the additions are assisted by concerted C-6-C-1 or C-7-C-1 bond migration corresponding to endo- and exo-side addition, respectively.Furthermore in β-fenchoisocamphorol (9) obtained in CF3COOD addition to 2, the fraction of deuterium at C-1 (0.40) exceeds that at C-2-endo (0.36) as shown in the 2H NMR spectrum.The same result is observed in 9 from model compounds 17 and 18.These facts are interpreted as resulting either from an equilibrium between the cation intermediates I and II, in which II is favored due to the secondary α-deuterium isotope effect on I, or from an isotopic perturbation of resonance in a bridged structure, which favors product formation with deuterium at C-1.
View MoreGuangzhou Probig Fine Chemical Co., Ltd.
Contact:020-86297874
Address:No.2, 1/F, No.20, Hetai Road,Hebian Village, Baiyun District,Guangzhou,China
Hangzhou Think Chemical Co. Ltd
website:http://www.thinkchem.com/
Contact:86-571-89986307/81956191/81956084/81956192
Address:Room 501-502, Tower E, Yuanjian Building, Yuanyang International Center, Hangzhou-310011, China
Zhejiang Chemicals Import & Export Corporation (ZHECHEM)
Contact:+86-571-87046953
Address:No. 37, Qingchun Road
Golden Union Agrochemical Import and Export Co., Ltd.
Contact:86-755-23910527
Address:Room 1106, Tower 3A, Excellence Century Center, Futian District, Shenzhen, China
Nanjing Raise Pharmatech Co., Ltd
website:http://www.raisechem.com
Contact:+86-25-58649566
Address:B381,No.606,Ningliu Road,Jiangbei New Area,Nanjing,Jiangsu Province,China
Doi:10.1039/c5gc01584g
(2016)Doi:10.1021/ja01145a538
(1951)Doi:10.1055/s-2003-42490
(2004)Doi:10.1016/S0022-328X(00)88984-6
(1981)Doi:10.1021/np970191s
(1997)Doi:10.1007/s10973-012-2725-4
(2013)