tert-butylcyanoketene-substituted styrene cycloadditions. A kinetic study

Sk Asrof Ali; Mohammed Muqtar; Abdulrahman H. Al-Husaini

doi:10.1039/p29950001001

tert-butylcyanoketene-substituted styrene cycloadditions. A kinetic study

Sk Asrof Ali^*, Mohammed Muqtar, Abdulrahman H. Al-Husaini

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

5 Scopus citations

Abstract

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 p 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.

Original language	English
Pages (from-to)	1001-1006
Number of pages	6
Journal	Journal of the Chemical Society. Perkin Transactions 2
Issue number	5
DOIs	https://doi.org/10.1039/p29950001001
State	Published - 1995

ASJC Scopus subject areas

General Chemistry

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title = "tert-butylcyanoketene-substituted styrene cycloadditions. A kinetic study",

abstract = "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 p 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.",

author = "Ali, \{Sk Asrof\} and Mohammed Muqtar and Al-Husaini, \{Abdulrahman H.\}",

year = "1995",

doi = "10.1039/p29950001001",

language = "English",

pages = "1001--1006",

journal = "Journal of the Chemical Society. Perkin Transactions 2",

issn = "0300-9580",

number = "5",

}

TY - JOUR

T1 - tert-butylcyanoketene-substituted styrene cycloadditions. A kinetic study

AU - Ali, Sk Asrof

AU - Muqtar, Mohammed

AU - Al-Husaini, Abdulrahman H.

PY - 1995

Y1 - 1995

N2 - 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 p 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.

AB - 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 p 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.

UR - https://www.scopus.com/pages/publications/37049069227

U2 - 10.1039/p29950001001

DO - 10.1039/p29950001001

M3 - Article

AN - SCOPUS:37049069227

SN - 0300-9580

SP - 1001

EP - 1006

JO - Journal of the Chemical Society. Perkin Transactions 2

JF - Journal of the Chemical Society. Perkin Transactions 2

IS - 5

ER -

tert-butylcyanoketene-substituted styrene cycloadditions. A kinetic study

Abstract

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