Categories: N/N Bond Formation >
Synthesis of Diazo Compounds
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Recent Literature
"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.
A Bi(V) compound catalyzes an oxidation of hydrazones into diazo compounds in
the presence NaBO3·H2O as the terminal oxidant. Ph3Bi(OAc)2
as catalyst is in situ generated from BiPh3 and AcOH. The reaction
was applied for the synthesis of diazocarbonyls and 2,2,2-trifluoromethyl
diazoalkanes in very good yields.
N. Tanbouza, L. Caron, A. Khoshoei, T. Ollevier, Org. Lett.,
2022, 24, 2675-2678.
An electrochemical synthesis provides diazo compounds from hydrazones in very
high yields and avoids the use of harsh and toxic chemical oxidants. This
reaction is practically simple to set up, offers mild conditions, and is highly
electron efficient (3 F/mol).
N. Tanbouza, A. Petti, M. C. Leech, L. Caron, J. M. Walsh, K. Lam, T.
Ollevier, Org. Lett.,
2022, 24, 4665-4663.
Alkynyl hydrazones can be conveniently synthesized from 2-oxo-3-butynoates and
hydrazine without formation of pyrazoles. The resultant
hydrazones are transformed into alkynyl diazoacetates under mild oxidative conditions in excellent yields. Further,
alkynyl cyclopropane and
propargyl silane carboxylates are synthesized in good yields using copper-catalyzed alkynyl carbene transfer reactions.
A. Sharma, P. Jamwal, H. Vaid, R. Gurubrahamam, Org. Lett., 2023, 25,
1889-1894.
"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.
The reaction of 1-aryl-2,2,2-trifluorodiazoethanes with alkenes provides
trifluoromethyl-substituted cyclopropanes with high diastereoselectivity and
enantioselectivity in the presence of an adamantylglycine-derived dirhodium
complex Rh2(R-PTAD)4 as catalyst.
J. R. Denton, D. Sukumaran, H. M. L. Davies, Org. Lett., 2007,
9, 2625-2628.