A novel method to access chiral nonnatural 2,4-disubstituted pyrrolidines from aldehydes and nitroolefins only with an α-substituent was written by Zheng, Bo;Wang, Hui;Han, Yong;Liu, Changlu;Peng, Yungui. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2013.Reference of 14425-64-0 This article mentions the following:
α-Substituted-γ-nitropentanals I [R = Me2CH, Me(CH2)n, Ph; R1 = Ph, 4-MeOC6H4, 2-ClC6H4, 3-ClC6H4, 2-BrC6H4, H, TBDMSO; n = 1-7; TBDMS = tert-butyldimethylsilyl] [or ent-I (R = EtCH2; R1 = TBDMSO)] were prepared in 56-86% yields, in 79:21-99:1 dr, and in 70-98% ee by addition of aldehydes RCH2CHO to α-substituted nitroalkenes R1CH2C(NO2):CH2 in the presence of a nonracemic N-siloxypyrrolidinylmethyl triflimide II (TBDPS = tert-butyldiphenylsilyl; Tf = F3CSO2) and 4-nitrobenzoic acid in DMF. Reduction of the nitro groups of I (R = Me2CH, EtCH2, PhCH2; R1 = Ph, TBDMS) followed by intramol. reductive amination yielded the nonracemic pyrrolidines III (R = Me2CH, EtCH2, PhCH2; R2 = Ph, HO) in 46-70% yields and in 70-96% ee. In the experiment, the researchers used many compounds, for example, 1-(2-Bromoethyl)-4-methoxybenzene (cas: 14425-64-0Reference of 14425-64-0).
1-(2-Bromoethyl)-4-methoxybenzene (cas: 14425-64-0) belongs to organobromine compounds. Bromo compounds are employed in a variety of metal-catalyzed coupling reactions. They are also ideal candidates for the synthesis of Grignard reagents that have wide-applicability in organic synthesis. alpha-Bromoesters are employed in the Reformatsky reaction for the synthesis of beta-hydroxyesters. One prominent application of synthetic organobromine compounds is the use of polybrominated diphenyl ethers as fire-retardants, and in fact fire-retardant manufacture is currently the major industrial use of the element bromine.Reference of 14425-64-0
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary