A Pd(II)-Catalyzed Ring-Expansion Reaction of Cyclic 2-Azidoalcohol Derivatives: Synthesis of Azaheterocycles
作者:Shunsuke Chiba、Yan-Jun Xu、Yi-Feng Wang
DOI:10.1021/ja9049564
日期:2009.9.16
A Pd(II)-catalyzed ring expansion-reaction of cyclic 2-azidoalcohol derivatives was found to proceed via an unprecedented C-C bond cleavage-C-N bond formation sequence, providing substituted azaheterocycles.
发现 Pd(II) 催化的环状 2-叠氮醇衍生物的扩环反应通过前所未有的 CC 键断裂-CN 键形成序列进行,提供取代的氮杂杂环。
<i>N</i>-Silylenamines as Reactive Intermediates: Hydroamination for the Modular Synthesis of Selectively Substituted Pyridines
作者:Erica K. J. Lui、Daniel Hergesell、Laurel L. Schafer
DOI:10.1021/acs.orglett.8b02703
日期:2018.11.2
modular and selective synthesis of mono-, di-, tri-, tetra-, and pentasubstituted pyridines is reported. Hydroamination of alkynes with N-silylamine using a bis(amidate)bis(amido)titanium(IV) precatalyst furnishes the regioselective formation of N-silylenamines. Addition of α,β-unsaturated carbonyls to the crude mixtures followed by oxidation affords 47 examples of pyridines in yields of up to 96%
Intramolecular carbolithiation of <i>N</i>-allyl-ynamides: an efficient entry to 1,4-dihydropyridines and pyridines – application to a formal synthesis of sarizotan
作者:Wafa Gati、Mohamed M Rammah、Mohamed B Rammah、Gwilherm Evano
DOI:10.3762/bjoc.8.250
日期:——
developed a general synthesis of polysubstituted 1,4-dihydropyridines and pyridines based on a highly regioselective lithiation/6-endo-dig intramolecular carbolithiation from readily available N-allyl-ynamides. This reaction, which has been successfully applied to the formalsynthesis of the anti-dyskinesia agent sarizotan, further extends the use of ynamides in organic synthesis and further demonstrates
Synthesis of cis-3,4-diarylpiperidines and cis-3,4-diaryltetrahydropyrans
作者:Meng-Yang Chang、Chun-Yu Lin、Ching-Yi Hung
DOI:10.1016/j.tet.2007.02.055
日期:2007.4
following sequence: (1) pinacol-type ring contraction having the combination of m-chloroperoxybenzoic acid and boron trifluoride etherate, (2) Grignard addition with arylmagnesium bromide reagents and followed by boron trifluoride etherate-mediated intramolecular ring-expanded rearrangement, and (3) hydrogenation with hydrogen on 10% palladium-activated carbon. A facile synthesis of 3,4-diarylpyridines
efficient synthetic route to unsymmetrically substituted dihydropyridine scaffolds via dehydrative [4 + 2] cycloaddition of N-tosylated α,β-unsaturated imines with aldehydes has been developed. This transformation is enabled by (i) the remarkable catalytic ability of the cationic Ru(IV) porphyrin complex to activate both the imino and carbonyl groups and (ii) the hydrophobic nature of the porphyrin ligand,