LIC-KOR promoted formation of conjugated dienes as useful building blocks for palladium-catalyzed syntheses
作者:Annamaria Deagostino、Manuele Migliardi、Ernesto G. Occhiato、Cristina Prandi、Chiara Zavattaro、Paolo Venturello
DOI:10.1016/j.tet.2005.01.044
日期:2005.3
It is demonstrated that α,β-unsaturated acetals can be considered a synthetic tool for transforming carbonyl derivatives into cheap and easily accessible starting materials for the construction of various and more complex structures. The lithium–potassium mixed superbase LIC-KOR induces a conjugate elimination reaction that converts α,β-unsaturated acetals into 1E-1-alkoxybuta-1,3-dienes. These derivatives
已经证明,α,β-不饱和缩醛可以被认为是用于将羰基衍生物转化成廉价且易于获得的起始材料以用于构建各种和更复杂的结构的合成工具。锂-钾混合超碱LIC-KOR引起共轭消除反应,该反应将α,β-不饱和缩醛转化为1 E -1-烷氧基丁1,3-二烯。这些衍生物可以很容易地就地金属化并通过与亲电试剂反应而官能化。结果可分为两部分:(1)烷氧基二烯基硼酸酯与四氢萘醌或异苯并二氢吡喃酮衍生的乙烯基三氟甲磺酸酯之间的钯催化交叉偶联反应;(2)在钯催化剂的存在下与芳基衍生物的区域和立体选择性交叉偶联反应(Heck条件)。
Palladium-Catalyzed Intramolecular Oxidative Heck Cyclization and Its Application toward a Synthesis of (±)-β-Cuparenone Derivatives Supported by Computational Studies
oxidative cyclization of substituted homoallylic alcohols to form cyclic keto compounds under palladium-catalyzed conditions is described. The reaction has practical applications in the synthesis of sesquiterpenes. The mechanism of cyclization, the key step in the tandemreaction, was analyzed by using density functional theory calculations. A novel and efficient intramolecular oxidative cyclization of substituted
Palladium-Catalyzed Novel Cycloisomerization: An Unprecedented Domino Oxidative Cyclization towards Substituted Carbocycles
作者:Jayanta K. Ray、Devalina Ray、Sajal K. Mal
DOI:10.1055/s-2005-872241
日期:——
Efficient Pd-catalyzed cyclization of homoallylated β-bromo-vinylalcohols via a domino process to carbocycle derivatives in presence of different bases is reported. An unexpected and novel palladium-mediated Heck-type intramolecular oxidative cyclization of 1-bromohexa-1-ene-5-yn-3-ol derivatives is also described.
Three-carbon annelations. Regiocontrolled reactivity of trimethylsilyl- and ethoxyethyl-protected cyanohydrins. Versatile homoenolate and acyl anion equivalents
作者:Richard M. Jacobson、George P. Lahm、John W. Clader
DOI:10.1021/jo01291a005
日期:1980.2
Nasarow; Burmistrowa, Zhurnal Obshchei Khimii, 1950, vol. 20, p. 1310