Does the rate of competing isomerisation during alkene metathesis depend on pre-catalyst initiation rate?
نویسندگان
چکیده
Experimental studies of the ring-closing metathesis reaction of 1,8-nonadiene and the ROMP reaction of cycloheptene show that the rate of isomerisation is not correlated to the initiation rate of the pre-catalyst, and that the absence of phosphine leads to a greatly increased rate of isomerisation. A range of pre-catalysts and solvents were probed and it is proposed that the isomerisation is mediated by a ruthenium hydride complex; our results are consistent with the rate-determining formation of such a species, which might be trapped in situ by tricyclohexylphosphane.
منابع مشابه
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ورودعنوان ژورنال:
- Dalton transactions
دوره 43 12 شماره
صفحات -
تاریخ انتشار 2014