In the present work, arylethynes were studied as new C-nucleophiles in the asymmetric Mannich addition reactions with ()---butylsulfinyl-3,3,3-trifluoroacetaldimine. The reactions were conducted under operationally convenient conditions affording the corresponding Mannich adducts with up to 87% yield and 70:30 diastereoselectivity. The isomeric products can be separated using regular column chromatography to afford diastereomerically pure compounds. The purified Mannich addition products were deprotected to give the target enantiomerically pure trifluoromethylpropargylamines. A mechanistic rationale for the observed stereochemical outcome is discussed.
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| http://dx.doi.org/10.3762/bjoc.16.217 | DOI Listing |
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