125364-58-1Relevant articles and documents
Anchimeric assistance by γ-substituents Z, Z=MeO, PhO, MeS or PhS, in reactions of the bromides (Me3Si)2(ZMe2Si)CSiMe2Br with AgBF4
Eaborn, Colin,Kowalewska, Anna,David Smith,Stańczyk, Wlodziemierz A.
, p. 29 - 36 (2007/10/03)
The new organosilicon bromides (Me3Si)2(ZMe2Si)CSiMe2Br with Z=PhO or MeS have been prepared and new spectroscopic data obtained for the previously reported compounds with Z=H, F, Br, Me, Ph, MeO or PhS. Competitions between pairs of bromides for a deficiency of AgBF4 in Et2O, with the determination of the ratio of the fluoride products by 19F-NMR spectroscopy, have led to the following approximate relative reactivities of the bromides and so to the relative abilities of the γ-Z groups to provide anchimeric assistance to the leaving of Br- in this reaction: Me, 1; Ph, 40; PhO, 3400; PhS, 5000; MeS, 7000; MeO, 54 000. In methanolysis in CH2Cl2, (Me3Si)2(MeOMe2Si)CSiMe2Cl has been found to be roughly 120 times as reactive as (Me3Si)2(PhOMe2Si)CSiMe2Cl. Combination of the results with previously available information suggests the following approximate order of ability of γ-groups Z to provide anchimeric assistance in reactions at the Si-X bonds in compounds (Me3Si)2(ZMe2Si)CSiMe2X: OCOMe>OMe>OCOCF3>MeS>PhS, PhO>N3, Cl>NCS>Ph>CH=CH2>Me.
Preparation of the iodides (Me3Si)2C(SiMe2C6H4Y)(SiMe2I) and some related compounds
Eaborn, Colin,Jones, Karen L.,Lickiss, Paul D.
, p. 35 - 42 (2007/10/02)
The preparations of: (a) the iodides (Me3Si)2C(SiMe2C6H4Y)(SiMe2I) (Y=H, p-OMe, p-Me, p-Cl, m-CF3), via the corresponding hydrides; (b) the compounds (Me3Si)2C(SiMe2Ph)(SiMe2X) with X=F, O2CCF3, OMe, N3, NCS and Cl: and (c) the iodide (p-MeC6H4)3CSiMe2I are described. Key words: Silicon; Iodide; Fluoride; Hydride; Trimethylsilyl
Reaction of (Me3Si)2C(SiMe2Ph)(SiEt2I) with AgBF4. 1,3-Migration of the Phenyl Group
Eaborn, Colin,Lickiss, Paul D.,Najim, Sabah T.,Stanczyk, Wlodzimierz A.
, p. 59 - 62 (2007/10/02)
The reaction of (Me3Si)2C(SiMe2Ph)(SiEt2I) with AgBF4 in Et2O has been shown to give a ca. 2:3 ratio of the unrearranged (Me3Si)2C(SiMe2Ph)(SiEt2F) and the rearranged (Me3Si)2C(SiEt2Ph)(SiMe2F).The reaction is thought to proceed via a cation, II, in which
Anchimeric Assistance by γ-Aryl Groups in Solvolysis of Organosilicon Iodides. Some Remarkably Large Remote Substituent Effects
Eaborn, Colin,Jones, Karen L.,Lickiss, Paul D.
, p. 595 - 596 (2007/10/02)
The very large spread of rates in reactions of the iodides (Me3Si)2C(SiMe2C6H4X)(SiMe2I) (X = p-OMe, p-Me, H, p-Cl, or m-CF3) with (CF3)2CHOH and CF3CH2OH (the compound with X = p-OMe is 1.9E05 and 6.5E04 times, respectively, as reactive as that with X = m-CF3) is attributed to nucleophilic assistance by the aryl group to the leaving of the I- ion.