Enantioselective synthesis of allenic esters via an ylide route.
نویسندگان
چکیده
Pseudo-C2-symmetric chiral phosphorus ylides have been designed and synthesized for the enantioselective preparation of allenic esters, and up to 92% ee has been achieved.
منابع مشابه
Iron porphyrin-catalyzed olefination of ketenes with diazoacetate for the enantioselective synthesis of allenes.
The Wittig reaction and its variants are the most powerful approaches for constructing carbon-carbon double bonds in organic synthesis due to their unambiguous positioning and good stereoselectivity.1 Of the recent developments,2-4 much attention has been paid to ylide olefination of aldehydes3 and ketones4 under neutral conditions by transition metal complex-catalyzed decomposition of diazo co...
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Bestmann ylide [(triphenylphosphoranylidene)ketene] acts as a chemical linchpin that links nucleophilic entities, such as alcohols or amines, with carbonyl moieties to produce unsaturated esters and amides, respectively. In this work, the formation of α,β,γ,δ-unsaturated esters (dienoates) is achieved through the coupling of Bestmann ylide, an alcohol and an α,β-unsaturated aldehyde. Primary an...
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ورودعنوان ژورنال:
- Chemical communications
دوره 28 شماره
صفحات -
تاریخ انتشار 2006