Categories: C-N Bond Formation >
Synthesis of isocyanates
Recent Literature
Alkyl isocyanates are prepared in good to excellent yields by treatment of
alcohols, thiols and trimethylsilyl ethers with triphenylphosphine/2,3-dichloro-5,6-dicyanobenzoquinone/Bu4NOCN
in acetonitrile. This method is highly selective for conversion of primary
alcohols to alkyl isocyanates in the presence of secondary and tertiary alcohols,
thiols and trimethysilyl ethers.
B. Akhlaghinia, Synthesis, 2005,
1955-1958.
Related
A smooth and efficient oxidation of isonitriles to isocyanates by DMSO as the
oxidant is catalyzed by trifluoroacetic anhydride. The process is complete in a
few minutes, forming dimethyl sulfide as the only byproduct. The newly formed
isocyanates may be used directly or isolated in high purity by solvent
evaporation.
H. V. Le, B. Ganem, Org. Lett., 2011,
13, 2584-2585.
DMAP catalyzes a controllable, base-free, decarboxylative isocyanation of
carboxylic acids with 1,1-dimethyl-2,2,2-trichloroethoxycarbonyl azide (DMTN3).
The scope of this one-pot Curtius rearrangement covers a range of primary,
secondary, and tertiary alkyl and aryl carboxylic acids. Examples are reported
of late-stage modifications of natural products and drug molecules.
K. Lin, H. Lu, Org. Lett., 2023, 25,
4534-4539.
A catalytic amount of N-methylimidazole (NMI) accelerated a mild one-pot
synthesis of aromatic and aliphatic carbamates via the Lossen rearrangement.
Moreover, the utility of arylsulfonyl chloride in combination with NMI minimizes
the formation of often-observed hydroxamate-isocyanate dimers.
S. Yoganathan, S. J. Miller, Org. Lett., 2013,
15, 602-605.