Catalytic asymmetric C-N bond formation: phosphine-catalyzed intra- and intermolecular γ-addition of nitrogen nucleophiles to allenoates and alkynoates.
نویسندگان
چکیده
Pin the amine on the gamma: A new method has been developed for the γ-addition of nitrogen nucleophiles to γ-substituted alkynoates or allenoates through intra- and intermolecular processes that are catalyzed by spirophosphine 1. An asymmetric version of this reaction affords enantioenriched pyrrolidines, indolines, and γ-amino-α,β-unsaturated carbonyl compounds.
منابع مشابه
Enantioselective Carbon-Sulfur Bond Formation: γ Additions of Aryl Thiols to Allenoates Catalyzed by a Chiral Phosphepine.
An effective phosphine-catalyzed method has been developed for the enantioselective addition of aryl thiols to the γ position of allenoates, thereby furnishing ready access to aryl alkyl sulfides in very good ee. An array of mechanistic data are consistent with addition of the chiral phosphine to the allenoate being the turnover-limiting step of the catalytic cycle. The optimized reaction condi...
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Methods have recently been developed for the phosphine-catalyzed asymmetric γ-addition of nucleophiles to readily available allenoates and alkynoates to generate useful α,β-unsaturated carbonyl compounds that bear a stereogenic center in either the γ or the δ position (but not both) with high stereoselectivity. The utility of this approach would be enhanced considerably if the stereochemistry a...
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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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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:
- Angewandte Chemie
دوره 52 9 شماره
صفحات -
تاریخ انتشار 2013