Asymmetric carbon-carbon bond formation gamma to a carbonyl group: phosphine-catalyzed addition of nitromethane to allenes.
نویسندگان
چکیده
A chiral phosphine catalyzes the addition of a carbon nucleophile to the gamma position of an electron-poor allene (amide-, ester-, or phosphonate-substituted), in preference to isomerization to a 1,3-diene, in good ee and yield. This strategy provides an attractive method for the catalytic asymmetric gamma functionalization of carbonyl (and related) compounds.
منابع مشابه
Phosphine-catalyzed asymmetric additions of malonate esters to {gamma}-substituted allenoates and allenamides.
Because carbonyl groups are ubiquitous in organic chemistry, the ability to synthesize functionalized carbonyl compounds, particularly enantioselectively, is an important objective. We have developed a straightforward and versatile method for catalytic asymmetric carbon-carbon bond formation at the γ-position of carbonyl compounds, specifically, phosphine-catalyzed additions of malonate esters ...
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Because carbonyl groups are ubiquitous in organic chemistry, the ability to synthesize functionalized carbonyl compounds, particularly enantioselectively, is an important objective. We have developed a straightforward and versatile method for catalytic asymmetric carbon–carbon bond formation at the γ-position of carbonyl compounds, specifically, phosphine-catalyzed additions of malonate esters ...
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ورودعنوان ژورنال:
- Journal of the American Chemical Society
دوره 131 40 شماره
صفحات -
تاریخ انتشار 2009