CARBAMOYL HALIDES FROM THIURAM DISULFIDES
289
CONCLUSION
The present method describes a simple and efficient method for the synthesis of
0
commercially important N,N -substituted carbamoylchlorides from the correspond-
ing tetraalkyl thiuram disulfides, prepared from secondary alkyl amines and carbon
disulfide. The notable feature of this two-step preparation is that the process is econ-
omically viable (i.e., enhanced rate of reaction and negligible by-products), with a
cleaner reaction profile, which makes it a useful and attractive process for synthesis.
The generality and simple experimental and product isolation procedures are
expected to play an important role in the development of this new method. It is
an important step in the development of a greener and more efficient commercial
synthesis. This will certainly prove to be an important improvement over the
phosgenation method being used at present.
ACKNOWLEDGMENTS
The authors gratefully acknowledge CBMR, SGPGI, Lucknow, for NMR
spectra and CDRI, Lucknow, for IR spectra and elemental analysis. One of the
authors (K. Adeppa) wishes to convey his grateful feelings to India Pesticides Lim-
ited, Lucknow, India, for providing all laboratory facilities and financial support,
which made it possible to complete the present work successfully.
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