Synthesis of 3,5-disubstituted pyrazoles via Cope-type hydroamination of 1,3-dialkynes.
نویسندگان
چکیده
An efficient method for the synthesis of 3,5-disubstituted pyrazoles is described. The reactions of 1,3-dialkynes with hydrazine proceeded smoothly in dimethyl sulfoxide under mild reaction conditions to produce 3,5-disubstituted pyrazoles in satisfactory to excellent yields. A one-pot procedure of the transformation has been developed.
منابع مشابه
A theoretical study on the mechanisms of the reactions between 1,3-dialkynes and ammonia derivatives for the formation of five-membered N-heterocycles.
The reactions between 1,3-dialkynes and ammonia derivatives (such as hydrazine and hydroxylamine) for the formation of five-membered N-heterocycles (i.e. 3,5-disubstituted pyrazole and 3,5-disubstituted isoxazole) have been investigated using the density functional theory (DFT) method. The calculated results indicate that the favorable mechanism of this kind of reaction generally contains four ...
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ورودعنوان ژورنال:
- Organic letters
دوره 14 9 شماره
صفحات -
تاریخ انتشار 2012