117909-19-0Relevant academic research and scientific papers
Cycloaddition of Moore's ketene to 4-substituted styrenes
Gheorghiu, Mircea D.,Parvulescu, Luminitza,Draghici, Constantin,Mihai, Marina,Popescu, Angela
, p. 283 - 289 (2007/10/03)
Products of the reaction of t-butylcyanoketene (TBCK, Moore's ketene) with 4-nitro-, 4-methoxy-, 4-fluoro- and 4-chlorostyrene are presented. Based on the analysis of reaction products we propose a stepwise reaction mode for the cases of 4-methoxy, 4-fluoro- and 4-chlorostyrene; 4-nitrostyrene reacted in a 2πb + 2π a concerted mode.
tert-Butylcyanoketene-substituted styrene cycloadditions. A kinetic study
Ali, Sk. Asrof,Muqtar, Mohammed,Al-Husaini, Abdulrahman H.
, p. 1001 - 1006 (2007/10/02)
Rate constants for the cycloaddition of tert-butylcyanoketene (TBCK) 1 with various substituted styrenes at different temperatures have been determined by 1H NMR spectroscopy.The addition reaction afforded contra-thermodynamic adducts 3 stereoselectively; a way has been found to convert adducts 3 into thermodynamic cyclobutanones 4.The activation parameters of cycloadditions along with the Hammett reaction constant ρ and the solvent effect on cycloreversion of 3 indicate a concerted asynchronous mechanism involving a transition state with some degree of charge separation.An approximate difference in the energy of activation between the favourable and unfavourable mode of TBCK-p-methoxystyrene addition has been determined to be 10.6 kJ mol-1.
Study of ketene-alkene cycloadditions and cycloreversions of cyclobutanones
Al-Husaini,Muqtar,Ali Sk.
, p. 7719 - 7726 (2007/10/02)
A study of the addition reaction of tert-butylcyanoketene (TBCK) with several alkenes and thermal cycloreversion of various TBCK-alkene adducts in different solvents has been carried out. Cycloreversions were usually found to follow a concerted pathway.
