کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1325968 977412 2010 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Synthesis and fluxional behaviour of new “heavy fluorous” cyclopentadienes
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی معدنی
پیش نمایش صفحه اول مقاله
Synthesis and fluxional behaviour of new “heavy fluorous” cyclopentadienes
چکیده انگلیسی

The new “heavy fluorous” cyclopentadienes C5H6−n[M(C2H4C6F13)3]n (M = Si, n = 1 (3); n = 2 (4) and M = Sn, n = 1 (10)) were synthesized by reaction of cyclopentadienyl lithium with BrSi(C2H4C6F13)3 (2) or commercial BrSn(C2H4C6F13)3. Fluorous cyclopentadienes prepared in this manner contain three or six C6F13 groups, which significantly increase their solubility in perfluorinated solvents. They also provide intermediates for titanium complexes suitable for fluorous biphase catalysis. All three isomers of silylcyclopentadienes 3 and 4 were identified and fully characterized by two dimensional NMR spectroscopy, which was performed at low temperature. The allylic isomers 3a and 4a undergo degenerate metallotropic rearrangement. This fluxional behaviour was compared with the behaviour of previously prepared cyclopentadienes 6 and 7 (C5H6−n[SiMe2(C2H4C8F17)]n where n = 1, 2, respectively). The presence of allylic isomers 6a and 7a was further confirmed by Diels-Alder cycloaddition of the strong dienophile tetracyanoethylene (TCNE), providing compounds 8 and 9.

The synthesis and fluxional behaviour of new “heavy fluorous” cyclopentadienes, substituted with three and six ponytails, is reported. Special emphasis is placed on the assignment of individual isomers and their interconversion.Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Organometallic Chemistry - Volume 695, Issue 4, 15 February 2010, Pages 537–545
نویسندگان
, , , ,