Thermal rearrangements of cyclic amine ylides. VIII. Intramolecular cyclization of 2-ethynylpyridine N-ylides into indolizines and cycl(3.2.2)azines.
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چکیده
منابع مشابه
The Photochemistry of Aromatic - N . - Ylides . Rearrangement and Fragmentation Patterns
Rearrangement and fragmentation patterns, which have been observed during uv. irradiation of the following pyridinium ylides, will be discussed: pyridinium methylides, N.-iminopyridinium ylides and pyridine-N--oxides. As a rule these mesoionic compounds undergo two competing reactions: i) photolytic cleavage via a triplet state, leading to the corresponding pyridines and to carbenes, nitrenes a...
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[reaction: see text] A bifunctional AgOAc-catalyzed asymmetric cycloaddition of azomethine ylides with electronic-deficient alkenes was developed using ferrocenyloxazoline-derived N,P ligands. The reactive metal-bound azomethine ylide dipole is formed by the deprotonation with acetate, and extra base is not necessary. The reactions proceed with high enantioselectivity. This method provides an e...
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The Cu-catalyzed intramolecular CH insertion of phenyliodonium ylide 5b has been investigated at 0° C in the presence of several chiral ligands. Enantioselectivities vary in the range of 38–72 %, and are higher than those resulting from reaction of the diazo compound 5c at 65° C. The results are consistent with a carbenoid mechanism for Cu-catalyzed decomposition of phenyliodonium ylides.
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ژورنال
عنوان ژورنال: Chemical and Pharmaceutical Bulletin
سال: 1988
ISSN: 0009-2363,1347-5223
DOI: 10.1248/cpb.36.3826