1159097-41-2Relevant academic research and scientific papers
Target-directed organocatalysis: A direct asymmetric catalytic approach to chiral propargylic and allylic fluorides
Jiang, Hao,Falcicchio, Aurelia,Jensen, Kim L.,Paixao, Marcio W.,Bertelsen, Soeren,Joergensen, Karl Anker
supporting information; experimental part, p. 7153 - 7157 (2009/09/30)
A simple, direct one-pot organocatalytic approach to the formation of optically active propargylic fluorides Is presented. The approach Is basedon organocatalytic a-fluorination of aldehydes and trapping and homolog ation of the Intermediate providing optically active propargylic fluorides In good yields and enantioselectivities up to 99percent ee. The procedure takes place by addition of NFSI, In the presence of 2-[bls(3,5-bls-trifluoromethylphenyl) trimethylsilyloxymethyl]pyrrolidine (as low as 0.25 mol percent) as the catalyst, to aldehydes In combination with dimethyl 2-oxopropylphosphonate and 4-acetamidobenzenesulfonyl azide. The scope of the reaction Is demonstrated by the formation of a number of optically active propargylic fluorides. It Is also shown that optically activefluoro-containing triazoles can be obtained In one-pot procedures from aldehydes using click-chemistry. Furthermore, Important coupling and mul ticomponent reactions of the optically active propargylic fluorides can be performed without affecting the enantiomeric excess. The direct one-pot formation of optically active allylic fluorides from aldehydes Is also demonstrated. Finally, the mechanisms for both the formation of the propargylic and allylic fluorides are outlined. 2009 American Chemical Society.
