aldehydes in the presence of 10 mol % Sc(OTf)3 gave the corresponding trans- and cis-fused 1,5-ditosyl-octahydro-1H-pyrrolo[3,2-c]pyridines, respectively, in good yields via intramolecular aza-Prinscyclization, whereas the coupling of (E)- and (Z)-N-(6-hydroxyhex-3-enyl)-4-methylbenzenesulfonamide afforded the corresponding trans- and cis-fused octahydro-1-tosylpyrano[4,3-b]pyrroles derivatives, respectively
的耦合(ë) -和(Ž)中的10摩尔%的存在-己-3-烯-1,6- ditosylamide与各种醛钪(OTF)3,得到相应的反式-和顺式-融合1,5- -二甲苯基-八氢-1 H-吡咯并[3,2- c ]吡啶分别通过分子内氮杂-Prins环化获得高收率,而(E)-和(Z)-N-(6-羟基己基-丁-3-烯基)-4-甲基苯磺酰胺,得到相应的反式-和顺-融合八氢-1- tosylpyrano [4,3- b]吡咯衍生物,分别通过分子内Prins环化。
Versatile Intramolecular Aza-Prins and Prins Cyclization of Aryl Epoxides: A Facile Synthesis of Diaza-, Oxa-aza-, and Dioxa-bicycles
作者:Jillu S. Yadav、Prashant Borkar、P. Pawan Chakravarthy、Basi V. Subba Reddy、Akella V. S. Sarma、Shaik Jeelani Basha、Balasubramanian Sridhar、René Grée
DOI:10.1021/jo902683p
日期:2010.3.19
Aryl epoxides undergo coupling smoothly with (E)-hex-3-ene-1,6-ditosylamide in the presence of 10 mol % p-TSA in 1,2-dichloroethane at 75 degrees C to produce the corresponding 1,5-ditosyl-octahydro-1H-pyrrolidino-[3,2-c]pyridines in good yields with high trans-selectivity, whereas the coupling of (Z)-hex-3-ene-1,6-ditosylamide gave cis-fused octahydro-1H-pyrrolidino[3,2-c]pyridines predominantly. The use of readily available p-TSA makes this method simple, convenient, and practical.
Fused tetracycles with a benzene or cyclohexadiene core: [2 + 2 + 2] cycloadditions on macrocyclic systems
A series of fused tetracycles with a benzene or cyclohexadiene core (2a–h) is satisfactorily prepared by intramolecular [2 + 2 + 2] cycloadditions of triynic and enediynic macrocycles (1a–h) under RhCl(PPh3)3 catalysis; the enantioselective cycloaddition of macrocycles1b and 1e gives chiral tetracycles with moderate enantiomeric excess.
Advancing Palladium-Catalyzed C−N Bond Formation: Bisindoline Construction from Successive Amide Transfer to Internal Alkenes
作者:Kilian Muñiz
DOI:10.1021/ja075655f
日期:2007.11.28
to internal alkenes affords the construction of vicinaldiamines. In the presence of a palladium catalyst, the reaction proceeds through two mechanistically different C-N bond formation reactions. It is initiated by aminopalladation, followed by a reductive amination of a palladated secondary carbon. The overall process proceeds with complete selectivity for both steps and thereby generates a convenient