Catalytic Activity Dependency on Catalyst Components in Aerobic Copper-TEMPO Oxidation
作者:Esa T. T. Kumpulainen、Ari M. P. Koskinen
DOI:10.1002/chem.200901245
日期:2009.10.19
The influence of catalystcomponents in the copper–TEMPO (2,2,6,6‐tetramethylpiperidine N‐oxide) catalysed aerobicoxidation of alcohols was investigated. The type and amount of base greatly influences reactivity. The bipyridyl ligand concentration had no major influence on catalysis, but excessive amounts led to a decrease in activity for longer reaction times. The kinetic dependency for TEMPO was found
Towards the total synthesis of calyculin C: preparation of the C9–C25 spiroketal-dipropionate unit
作者:Damien Habrant、Ari M. P. Koskinen
DOI:10.1039/c0ob00092b
日期:——
An asymmetric synthesis of the C9–C25 spiroketal fragment of calyculin C is described. Key steps include two crotylation reactions using successively Brown's reagent and (Z)-crotyltrifluorosilane for the formation of the anti, anti, anti stereotetrad, ynone formation by a Pd-catalyzed coupling of a thiol ester with a terminal alkyne and a double intramolecular hetero-Michael addition for the stereoselective
C 9 -C 25螺酮片段的不对称合成。钙调蛋白C描述。关键步骤包括依次使用布朗氏试剂进行两个crotylation反应和(Z)-巴豆基三氟硅烷为了形成抗,抗,抗立体四烯酮,是通过Pd催化的巯基酯与末端炔烃的偶合和双分子内杂-迈克尔加成反应形成的,用于spiroketal构架的立体选择性。