Pyrazole carbene chromium complex

Straightforward access to pyrazole carbene chromium complex LXI results from the 1,3-dipolar addition of diazo compounds to acetylenic chromium carbene LX the reagent thus obtained is a useful synthon for the preparation of novel heterocyclic systems such as pyrazole [1, 5-a]pyridine quinone LXIII derivatives [100] in low to moderate yield (10-51 o) according to the substituents (Figure 5). 

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