An easy preparation of per- and poly-fluoroalkyl propenyl sulfones
摘要:
Sodium tridecafluorohexanesulfinate (1a) and sodium 1-chloro-2,2,2-trifluoroethanesulfinate (1b) were prepared by the treatment of 1-iodo-tridecafluorohexane and 1-bromo-1-chloro-2,2,2-trifluoroethane with sodium dithionite in a water-acetonitrile solution. Prolonged reaction of 1a with allyl bromide in DMF afforded tridecafluorohexane 1-propenyl sulfone 2 as the only product in good yield. A similar treatment of 1b gave exclusively 1-chloro-2,2,2-trifluoroethane 3-propenylsulfone 4. Bromination of 4 followed by dehydrobromination with Et3N resulted in a mixture of 1-chloro-2,2,2-trifluoroethane 3-bromo-1-propenyl sulfone 6 and 1-chloro-2,2,2-trifluoroethane 2-bromo-3-propenyl sulfone 7, while dehydrobromination with pyridine gave sulfone 6 practically as the only product. alpha,beta-Unsaturated sulfones 2 and 6 were shown to be active dienophiles. (C) 2005 Elsevier B.V All lights reserved.
Insight into “entrainment” in SRN1 reactions of 2,2-dichloro-1,1,1-trifluoroethane(HCFC-123) with thiolates initiated by Na2S2O4
作者:Xiao-Jun Tang、Qing-Yun Chen
DOI:10.1016/j.jfluchem.2014.10.006
日期:2015.1
An interesting entrainment process in S(RN)1 reactions of 2,2-dichloro-1,1,1-trifluoroethane (HCFC-123) with thiolates were studied by experiments and DFT calculations. The radical-anion intermediate, generated from coupling of the fluorinated radical with the thiolate was considered as the key intermediate in this reaction. (C) 2014 Elsevier B.V. All rights reserved.
HUANG, WEI-YUAN;CHEN, JIAN-LONG, ACTA CHIM. SIN., 45,(1987) N 5, 445-449