A highly diastereoselective pinacol coupling reaction of aldehydes and ketones using low-valence niobium generated from Nb(V).
نویسندگان
چکیده
A simple method for the diastereoselective synthesis of racemic 1,2-diol mediated by low-valence niobium generated in situ is described. A 1,4-dioxane-toluene solvent system was found to be essential to achieve higher selectivities and to prevent other reactions of pinacols, such as deoxygenation and acetal formation. Aromatic aldehydes and ketones were converted to the corresponding pinacols with up to 97 and 85% de, respectively.
منابع مشابه
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ورودعنوان ژورنال:
- Chemical & pharmaceutical bulletin
دوره 52 2 شماره
صفحات -
تاریخ انتشار 2004