Journal of Organic Chemistry p. 5230 - 5234 (1994)
Update date:2022-08-03
Topics: Paal-Knorr Synthesis Synthesis of Alkyl Pyrrolylacetates Synthesis of Dialkyl Pyrrolylmalonates
Schloemer, George C.
Greenhouse, Robert
Muchowski, Joseph M.
N-Pyrrolylmagnesium halides (1, 2) react with alkyl bromoacetates (3a-d) in THF solution to give alkyl 2-pyrrolylacetates (5a-d) in good yields and with very high positional selectivity (C-2:C-3 >/= 25).The high regioselectivity is rationalized in terms of an increased propinquity between C-2 and the bromoacetate methylene group as a consequence of coordination between magnesium and the carbonyl oxygen of the alkylating agent. (2,5-Dimethylpyrrol-N-yl)magnesium chloride (9) and isopropyl bromoacetate (3c) gave the 3-pyrrolylacetate 10 exclusively.Alkoxycarbonylation of the dianions of the above alkyl pyrrolylacetates with alkyl chloroformates gave the corresponding dialkyl pyrrolylmalonates, two of which (16a and 19) were transformed into the dialkyl 1,2-dihydro-3H-pyrrolo<1,2-a>pyrrole-1,1-dicarboxylates (22 and 20, respectively) with 1,2-dichloroethane under phase transfer conditions.Compound 20 was converted into the powerful nonaddicting analgesic ketorolac (21).
View MoreHangzhou Taiyan Trading Co., Ltd
Contact:+86-13777583958
Address:NO.63, Xingyi Street, Xihu District, Hangzhou, Zhejiang, China
Contact:410-273-7300; 800-221-3953
Address:4609 Richlynn Dr., PO Box 369, Belcamp, MD, 21017-0369, USA
Suzhou Credit International Trading Co., Ltd
Contact:+86-512-65398039
Address:Qingdeng, Hightech. District, Suzhou
Contact:86-0510-85133006
Address:hubin road NO157
website:http://www.herbpurify.com
Contact:0086-028-85249238
Address:Room709-C1,Incubator Building, Tianfu Life Science Park No.88,Keyuan Road,Gaoxin district,Chengdu City,Sichuan Prov,China
Doi:10.1021/acs.orglett.5b02902
(2015)Doi:10.1021/ol5003016
(2014)Doi:10.1016/j.molliq.2011.07.010
(2011)Doi:10.1016/0008-6215(94)80045-6
(1994)Doi:10.1055/s-1994-25552
(1994)Doi:10.1021/jm030062a
(2003)