21652-58-4Relevant articles and documents
Siloxane based syntheses of fluorous ethenes and their tandem Heck reactions with aryl iodides
Csapo, Agnes,Rabai, Jozsef
, p. 79 - 85,7 (2020/09/16)
Perfluoroalkyl-ethenes (RfnCHCH2, 6a-c; a, n = 4; b, n = 6; c, n = 8) were prepared in good isolated yields (67-89%) and high purity (GC assay > 98%) from various fluorinated organosilanes in fluoride-anion assisted protodesilylation reactions. The environmentally more benign 'KF/NEt3/H2O' reagent combination introduced here was found as an effective substitute for the commonly used tetrabutylammonium- fluoride trihydrate (TBAF·3H2O) as a fluoride source. Fluorous styrenes ((E)-RfnCHCHAr, 8) were then prepared in good isolated yields (58-93%/iodoarene) and purities (GC assay > 95%) with the Pd(0) catalyzed Heck coupling of iodoarenes (Ar-I, 7) and perfluoroalkyl-ethenes generated in situ by the fluoride assisted cleavage of (β-perfluoroalkyl- α-iodo-ethyl)-siloxane ([RfnCH2CH(I)SiMe 2]2O, 3) precursors in DMF solution at elevated temperatures. They are accessible by the one-pot reaction of dimethylvinylchlorosilane (CH2CHSiMe2Cl, 2) and perfluoroalkyl iodides (Rfn-I, 1) as we reported earlier. Similarly, the radical chain addition of C8F17I to CH 2CHSi(OMe)3 (9) gave (β-perfluorooctyl-α-iodo- ethyl)-trimethoxysilane ([C8F17CH2CH(I)]Si(OMe) 3, 10) in good yield, which then was reacted with silica gel in dry toluene to obtain an SiO2-bonded (perfluorooctyl)ethene surrogate [silica(O)3SiCH(I)CH2C8F17, 11]. The fluoride assisted cleavage of 11 and tandem Heck reaction with iodobenzene afforded the appropriate cross-coupled product (E)-C8F 17CHCHPh.
PROCESS FOR PRODUCING FLUORINATED (METH)ACRYLIC ESTER
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Page/Page column 9, (2010/11/25)
A mixture of fluoroalkyl iodides of the formula C2F5(CF2CF2)nI ( n is an integer of ≥0) wherein the sum of such fluoroalkyl iodides of n=3 and n=4 contained is ≥85 mol% is provided. This mixture is subjected to an ethylene addition step and an esterification step, and C2F5(CF2CF2)nCH=CH2 and C2F5(CF2CF2)nCH2CH2OH are removed. Thus, there can be obtained a mixture of fluorine-containing (meth)acrylic esters of the formula C2F5(CF2CF2)nCH2CH2OCOCR1=CH2 (wherein R1 represents a hydrogen atom or a methyl group, and n is an integer of ≥0) wherein the content of impurities (namely, olefins of the formula C2F5(CF2CF2)nCH=CH2 and alcohols of the formula C2F5(CF2CF2)nCH2CH2OH) is low.
PROCESS FOR PRODUCING FLUORINATED ACRYLIC ESTER
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Page/Page column 8-9, (2008/06/13)
A mixture of fluorine-containing acrylic esters represented by CF3(CF2)nCH2CH2OCOCR1=CH2 wherein R1 is a hydrogen atom, a methyl group or a halogen atom and "n" is an integer of at least zero is subjected to distillation under such conditions that the esters are not polymerized, so as to give a mixture of the esters with a less content of impurities (that is, olefins represented by CF3(CF2)nCH=CH2 and alcohols represented by CF3(CF2)nCH2CH2OH) at a high yield.