Catalytic asymmetric [2,3] sigmatropic rearrangement of sulfur ylides generated from carbenoids and propargyl sulfides
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چکیده
Catalytic asymmetric [2,3] sigmatropic rearrangement of sulfur ylides generated from aryldiazoacetates and propargyl sulfides with a number of chiral Rh(II) and Cu(I) catalysts have been investigated and moderately high enantioselectivities (up to 81% ee) have been achieved. © 2003 Elsevier Science Ltd. All rights reserved.
منابع مشابه
Catalytic asymmetric [2,3]-sigmatropic rearrangement of sulfur ylides generated from copper(I) carbenoids and allyl sulfides.
Catalytic asymmetric sulfur ylide [2,3]-sigmatropic rearrangement of carbenoids generated from aryldiazoacetates has been investigated with a number of chiral Rh(II) and Cu(I) catalysts, and moderately high enantioselectivity (52-78% ee) can be achieved with Cu(MeCN)(4)PF(6)/2,2'-isopropylidenebis[(4S)-4-tert-butyl-2-oxazoline].
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Introduction Since their discovery in the late 1960s, the [2,3]-sigmatropic rearrangements of sulfonium ylides have received considerable attention because of their applications in organic synthesis and their probable involvement in biochemical processes. The most common method for sulfonium ylide generation involves the removal of a proton from a sulfonium salt with a strong base. However, a m...
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The [2,3]- and [1,2]-sigmatropic rearrangements of ammonium ylides are studied by a combination of experimental, standard computational, and dynamic trajectory methods. The mixture of concerted [2,3] rearrangement and bond cleavage observed experimentally is accounted for by the outcome of trajectories passing through the formal [2,3] rearrangement transition state. In this way the bond cleavag...
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