ISSN:
1434-193X
Keywords:
Ab initio calculations
;
Reaction mechanisms
;
Ketenes
;
Cumulenes
;
Cycloaddition reactions
;
Nucleophilic additions
;
Electrophilic addition
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The properties and reactivities of ketene, thioketene, and selenoketene were studied using the G2(MP2) level of theory. Calculated structures, vibrational frequencies, dipole moments, NMR chemical shifts, and charge distributions strongly suggest that thioketene and selenoketene are best represented by the neutral cumulenic form. Four prototype reactions were examined: ketene-ynol rearrangement, electrophilic and nucleophilic addition, and [2+2] cycloaddition. Thioketene and selenoketene were found to be more reactive than ketene in all reactions. In terms of chemistry, thioketene resembles selenoketene more than ketene. The variation of reactivity can readily be explained in terms of strain energy, electronegativity, and molecular orbital arguments.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
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