Chemistry - A European Journal p. 14593 - 14602 (2011)
Update date:2022-09-26
Topics:
Hata, Takeshi
Sujaku, Shiro
Hirone, Naoki
Nakano, Kirihiro
Imoto, Junsuke
Imade, Haduki
Urabe, Hirokazu
Treatment of ethyl (E)-5,5-bis[(benzyloxy)methyl]-8-(N,N-diethylcarbamoyl)- 2-octen-7-ynoate with an iron reagent generated from FeCl2 and tBuMgCl in a ratio of 1:4 (abbreviated as FeCl2/4 tBuMgCl) afforded ethyl [4,4-bis[(benzyloxy)methyl]-2-[(E)-(N,N-diethylcarbamoyl)methylene] cyclopent-1-yl]acetate in good yield. Deuteriolysis of an identical reaction mixture afforded the bis-deuterated product ethyl [4,4-bis[(benzyloxy)methyl]-2- [(E)-(N,N-diethylcarbamoyl)deuteriomethylene]cyclopent-1-yl]deuterioacetate, thus confirming the existence of the corresponding dimetalated intermediate. The latter intermediate can react with halogens or aldehydes to facilitate further synthetic transformations. The amount of FeCl2 was reduced to catalytic levels (10 mol% relative to enyne), and catalytic cyclizations of this sort proceeded with yields comparable to those of the aforementioned stoichiometric reactions. The cyclization of diethyl (E,E)-2,7-nonadienedioate with a stoichiometric amount of FeCl2/4 tBuMgCl, followed by the addition of sBuOH as a proton source, afforded a mixture of 2-(ethoxycarbonyl)- 3-bicyclo[3.3.0]octanone and its enol form in good yield. The use of aldehyde or ketone in place of sBuOH afforded 2-(ethoxycarbonyl)-3-bicyclo[3.3.0]octanone, which has an additional hydroxyalkyl side chain. Additionally, the metalation of a carbon-carbon unsaturated bond in N,N-diethyl-5,5-bis[(benzyloxy)methyl]-7,8- epoxy-2-octynamide or (E)-3,3-dimethyl-6-(N,N-diethylcarbamoyl)-5-hexenyl p-toluenesulfonate with FeCl2/4 tBuMgCl or FeCl2/4 PhMgBr was followed by an intramolecular alkylation with an epoxide or alkyl p-toluenesulfonate to afford 5,5-bis[(benzyloxy)methyl]-3-[(E)-(N,N- diethylcarbamoyl)methylene]-1-cyclohexanol or N,N-diethyl(3,3- dimethylcyclopentyl)acetamide after hydrolysis. In both cases, the remaining metalated portion α to the amide group was confirmed by deuteriolysis and could be utilized for an alkylation with methyl iodide.
View MoreContact:86-510-82853889
Address:Rm.3732, No.18-2,Yonghe Rd.,Wuxi,Jiangsu,214023,China
Qingdao XinYongAn Chemicals Co., Ltd
Contact:+86-532-81107967
Address:Chengyang dual-port industrial park by the sea,Qingdao
Suzhou Kangrun Pharmaceutical, Inc
Contact:86-512-63912376,63913329
Address:Building 2, No. 2358 ,Chang'an Rd, Wujiang Economic Development Zone Pioneering park, china
Changzhou Jiana Chemical Co.,Ltd
website:http://www.jianachem.com
Contact:86-0519-88731808
Address:Zhenglu Town Wujin City, Jiangsu Province
Xiamen Huasing Chemicals Co.Ltd.
Contact:0086-592-6228397
Address:NO.24, Xinglin North 2nd Road,Jimei district
Doi:10.1002/ardp.2503240809
(1991)Doi:10.1016/j.tetlet.2012.01.055
(2012)Doi:10.1039/c39910001173
(1991)Doi:10.1039/c2ob00003b
(2012)Doi:10.1134/S107042801202011X
(2012)Doi:10.1016/S0957-4166(00)86119-4
(1991)