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Synthesis of 3‐dialkylaminomethyl‐5‐methyl‐4‐substituted‐1 H ‐pyrazoles. Selective functionalization of one methyl group via n ‐nitration of 3,5‐dimethyl‐4‐substituted‐1 H ‐pyrazoles
Author(s) -
Lammers H.,
Vollinga R.,
Zandbergen P.,
CohenFernandes P.,
Habraken C. L.
Publication year - 1995
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570320309
Subject(s) - chemistry , nitration , substituent , acetonitrile , nitro , surface modification , medicinal chemistry , inert , organic chemistry , combinatorial chemistry , alkyl
Treatment of 4‐substituted 3,5‐dimethyl‐1‐nitro‐1 H ‐pyrazoles 1 and 10a‐c with secondary amines in acetonitrile, in the presence of 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU), affords the novel dialkyl‐aminomethyl‐1 H ‐pyrazoles 5, 6, 7, 8, 11a‐c, 12a‐c and 13a‐c in good to excellent yields. In this way one of the, in general, inert methyl groups of 3,5‐dimethyl‐4‐substituted‐1 H ‐pyrazoles is functionalized creating a new synthetic route to azoles containing a coordinating substituent.