Dimethyl sulfoxide, DMSO
Oxidation of alkynes to α-dicarbonyl derivatives through a convenient one-pot procedure via a Brřnsted acid-promoted "hydration" and a DMSO-based oxidation sequence has been achieved in high yields.
Z. Wan, C. D. Jones, D. Mitchell, J. Y. Pu, T. Y. Zhang, J. Org. Chem., 2006, 71, 826-828.
Selective and quantitative conversion of thiols to disulfides was effected by dimethyl sulfoxide under mild conditions catalyzed by dichlorodioxomolybdenum(VI).
R. Sanz, R. Aguado, M. R. Pedrosa, F. Arnáiz, Synthesis, 2002, 856-858.
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.
A one-pot tandem reaction of benzyl halides and o-aminobenzenethiol gives benzothiazoles in high chemical yields under mild conditions in DMSO in the absence of an additional oxidant. Both benzyl chlorides and bromides bearing a range of substituents proved to be suitable substrates.
C. Zhu, T. Akiyama, Synlett, 2010, 2345-2351.
Highly regio- and stereoselective reactions of readily available 2-(methoxycarbonyl)-2,3-allenols with oxalyl chloride in the presence of Et3N or DMSO afforded methyl 2-(ethynyl)alk-2(E)-enoates and 2-(1′-chlorovinyl)alk-2(Z)-enoates, respectively, in good yields.
Y. Deng, X. Kin, C. Fu, S. Ma, Org. Lett., 2009, 11, 2169-2172.
"Activated" dimethyl sulfoxide efficiently dehydrogenates hydrazones to the respective diazo compounds at -78°C. Under optimized conditions, simple vacuum filtration provides solutions of pure diazo compounds from which stable diazo species can be isolated in high yield, or that can be directly used in subsequent reactions.
M. I. Javed, M. Brewer, Org. Lett., 2007, 9, 1789-1792.