Mo(CO)6-Mediated Intramolecular Pauson−Khand Reaction of Substituted Diethyl 3-Allyloxy-1-Propynylphosphonates
摘要:
Cyclisation of diethyl 3-allyloxy-1-propynylphosphonates with MO(CO)(6) under PK conditions to give 3-substituted-5-oxo-3,5,6,6a-tetrahydro-1H-cyclopenta[c]furan-4-ylphosphonate, 2a-h, in 45-88% isolated yields was done. The R groups are always syn with H-b (where applicable). The stereochemistry was determined via both NMR and crystal X-ray analysis.
Powerful control by organoruthenium catalysts of the regioselective addition to C(1) or C(2) of the prop-2-ynyl ethers CC triple bond
作者:Henri Doucet、Nadine Derrien、Zahia Kabouche、Christian Bruneau、Pierre H. Dixneuf
DOI:10.1016/s0022-328x(97)00435-x
日期:1998.1
HCCCR2OMe towards carboxylic acids is controlled to regioselectively afford the functional enol esters R1CO2C(CH2)CR2OMe or R1CO2CHCHCR2OMe corresponding to the addition of the carboxylate to either C(2) or C(1) of the terminal triple bond, depending on the nature of the ruthenium catalyst precursor RuCl2(PPh3)(p-cymene) or Ru(η3-2-methylpropenyl)2(dppe), respectively.
Synthetic application of titanabicycles generated from 1,6- or 1,7-dienes, enynes, and diynes and (ν2-propene)Ti(O-i-Pr)2
作者:Hirokazu Urabe、Takeshi Hata、Fumie Sato
DOI:10.1016/0040-4039(95)00727-t
日期:1995.6
The title unsaturated compounds and a stoichiometric amount of (ν2-propene)Ti(O-i-Pr)2 afforded titanabicycles, which, upon hydrolysis, gave substituted cyclopentane and cyclohexane frameworks. The titanacycles could be also intercepted with deuterium, iodine, or carbon monoxide.
Mo(CO)<sub>6</sub>-Mediated Intramolecular Pauson−Khand Reaction of Substituted Diethyl 3-Allyloxy-1-Propynylphosphonates
作者:Dorit Moradov、Abed Al Aziz Al Quntar、Manar Youssef、Reem Smoum、Abraham Rubinstein、Morris Srebnik
DOI:10.1021/jo801988k
日期:2009.2.6
Cyclisation of diethyl 3-allyloxy-1-propynylphosphonates with MO(CO)(6) under PK conditions to give 3-substituted-5-oxo-3,5,6,6a-tetrahydro-1H-cyclopenta[c]furan-4-ylphosphonate, 2a-h, in 45-88% isolated yields was done. The R groups are always syn with H-b (where applicable). The stereochemistry was determined via both NMR and crystal X-ray analysis.
Cycloisomerization of Enynes via Rhodium Vinylidene-Mediated Catalysis
作者:Hahn Kim、Chulbom Lee
DOI:10.1021/ja052775j
日期:2005.7.1
A novel rhodium-catalyzed cycloisomerization has been developed which converts various acyclic enynes to their cyclic diene isomers with endoselectivity. Both [RhCl(COD)]2/P(4-FC6H4)3 and RhCl(PPh3)3 catalyst systems are effective in promoting the C-C bond-forming cyclization of enynes to furnish carbo- and heterocycles in good to excellent yield. Deuterium labeling studies suggest that the reaction
一种新型的铑催化的环异构化已被开发出来,它可以将各种无环烯炔转化为具有内选择性的环状二烯异构体。[RhCl(COD)]2/P(4-FC6H4)3 和 RhCl(PPh3)3 催化剂体系均能有效促进烯炔的 CC 键形成环化,从而以良好至极好的收率提供碳环和杂环。氘标记研究表明,该反应通过形成亚乙烯基铑,随后与烯烃进行 [2 + 2] 环加成和所得环丁烷开环来进行。这些机理研究重新评估了先前提出的反应途径,并导致发现了一种新的环异构化反应,该反应涉及环化时烯炔底物的炔烃上甲硅烷基和硒基取代基的迁移。