Abstract
A convenient one-step transformation of primary and secondary amines into the corresponding
unprotected guanidines using 4-benzyl-3,5-dimethyl-1H -pyrazole-1-carboxamidine and its polymer-bound variant is described. The scopes and
limitations of the method, the microwave-assistance of amidination as well as a recycling
protocol are examined.
Key words
amines - guanidines - polymer-bound reagent - microwave-assisted synthesis - reagent
regeneration
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