Thermolysis of Semicarbazones to the Corresponding Azines Through Reactive N-Substituted Isocyanate Intermediates
Abstract
:Introduction
Results and Discussion
- (Ia)
- undergoes π2s + π2a cycloaddition [17] giving the relatively unstable isocyanate dimer (Ib).
- (Ib)
- undergoes a threefold extrusion (2CO, N2) to give benzalazine (II).
Conclusion
Experimental
General
General Procedure for the Preparation of Azines (B) from Semicarbazones (A)
Spectral and Melting Point Data
Benzalazine 1B
p-Chlorobenzalazine 2B
p-Tolualdazine 3B
p-Nitrobenzalazine 4B
Bis(diethylamino)benzalazine 5B
3,4-Dimethoxybenzalazine 6B
Cyclohexanoneketazine 7B
Synthesis of 1-2 adducts (trapped products) 8, 9 and 10
Spectral and Melting Point Data
Benzylidene-N-decyl carbamate 8
4-n-Nonyloxy-benzylidene-N-decyl carbamate 9
[(4’-n-Dodecyloxy-benzaldehyde)- N-phenyl-(4-n-methoxy)] semicarbazone 10
Acknowledgements
References and Notes
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- Samples Availability: Available from the authors.
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Shah, S.N.; Chudgar, N.K. Thermolysis of Semicarbazones to the Corresponding Azines Through Reactive N-Substituted Isocyanate Intermediates. Molecules 2000, 5, 657-664. https://doi.org/10.3390/50400657
Shah SN, Chudgar NK. Thermolysis of Semicarbazones to the Corresponding Azines Through Reactive N-Substituted Isocyanate Intermediates. Molecules. 2000; 5(4):657-664. https://doi.org/10.3390/50400657
Chicago/Turabian StyleShah, S. N., and N. K. Chudgar. 2000. "Thermolysis of Semicarbazones to the Corresponding Azines Through Reactive N-Substituted Isocyanate Intermediates" Molecules 5, no. 4: 657-664. https://doi.org/10.3390/50400657