Pauson-Khand approach to chiral, diastereomerically pure group 4 ansa-metallocene complexes
摘要:
The C-2-symmetric bis(1,6-enynes) threo-1,10-diphenyl-5,6-divinyl-1,9-decadiyn and threo-9,1 0-divinyl-5,13-octadecadiyne undergo the intramolecular Pauson-Khand reaction regio- and stereoselectively to give C(2)symmetric bis(enones) with two bicyclo[3.3.0]octyl moieties joined at the C6 position. Experiments aimed at converting the bis(enones) into chiral, diastereopure ansa-bridged group 4 metallocene complexes are described. (C) 1999 Elsevier Science Ltd. All rights reserved.
由环丁酮和氯甲基对甲苯基亚砜合成的[氯(对甲苯甲硫基)亚甲基]环丁烷可分三步以高总收率进行处理,过量的氰基甲基锂则可以高产率得到烯腈。用乙酸中的H 3 PO 4加热这些烯腈,得到高产率的2-氰基双环[3.3.0] oct-1-en-3-one。另一方面,用氰基甲基锂处理[氯(对甲苯基亚磺酰基)亚甲基]环丁烷,然后将乙腈同系物的碳负离子锂化,得到在3-位具有取代基的烯氨基腈。用H 3 PO 4加热烯腈在乙酸中的乙酸得到高至高产率的2-取代的双环[3.3.0] oct-1-en-3-one。该方法提供了一种新颖且通用的方法,可从环丁酮以良好的总收率合成2-取代的双环[3.3.0] oct-1-en-3-ones。
substituent at the 3-position. Heating of the enaminonitriles with H3PO4 in acetic acid gave 2-substituted bicyclo[3.3.0]oct-1-en-3-ones in good to high yields. This method offers a novel and versatile procedure for synthesis of 2-substituted bicyclo[3.3.0]oct-1-en-3-ones from cyclobutanones in good overall yields.
由环丁酮和氯甲基对甲苯基亚砜合成的[氯(对甲苯甲硫基)亚甲基]环丁烷可分三步以高总收率进行处理,过量的氰基甲基锂则可以高产率得到烯腈。用乙酸中的H 3 PO 4加热这些烯腈,得到高产率的2-氰基双环[3.3.0] oct-1-en-3-one。另一方面,用氰基甲基锂处理[氯(对甲苯基亚磺酰基)亚甲基]环丁烷,然后将乙腈同系物的碳负离子锂化,得到在3-位具有取代基的烯氨基腈。用H 3 PO 4加热烯腈在乙酸中的乙酸得到高至高产率的2-取代的双环[3.3.0] oct-1-en-3-one。该方法提供了一种新颖且通用的方法,可从环丁酮以良好的总收率合成2-取代的双环[3.3.0] oct-1-en-3-ones。
Effect of coordinating ligands on the Pauson-Khand cycloaddition: trapping of an intermediate
作者:Marie E. Krafft、Ian L. Scott、Romulo H. Romero、Sabine Feibelmann、Craig E. Van Pelt
DOI:10.1021/ja00069a017
日期:1993.8
reaction, including reports that tertiary amineN-oxides greatly accelerate the rate of cycloaddition in both intra- and some intermolecular reactions. To date, there has been no direct evidence to support the mechanistic hypothese for either the thermal or amine oxide promoted reactions beyond complete identification of the hexacarbonyl alkyne complex. While the amine oxide promoted reaction is normally
Crosslink-cyclized cyclopentadiene and dihalobis type metal compound containing same as ligand
申请人:——
公开号:US20010012902A1
公开(公告)日:2001-08-09
A process for producing a crosslink-cyclized cyclopentadiene, comprising the steps of reacting a cyclopentenone with an alkali metal hydride to thereby reduce the cyclopentenone (reduction step A) into a cyclopentenol; and reacting the cyclopentenol with a dehydrating agent to thereby dehydrate the cyclopentenol (dehydration step B) into a crosslink-cyclized cyclopentadiene of the general formula (III):
1
wherein each of R
1
and R
2
independently represents a hydrogen atom or a linear or branched saturated alkyl group having 1 to 6 carbon atoms, n is an integer of 3 to 10, and the broken line in the 5-membered ring denotes that the 5-membered ring has two double bonds.
Acceleration of the thermal pauson-khand reaction by coordinating ligands
作者:Marie E. Kraff、Ian L. Scott、Romulo H. Romero
DOI:10.1016/s0040-4039(00)74796-4
日期:1992.6
Coordinating ligands in the homo- and bishomopropargylic position of a 1,6-enyne have been found to enhance the rate of the thermal Pauson-Khand cycloaddition.
Process for the preparation of condensed cyclopentadiene derivatives, 1, 3 disubstituted derivatives and metallocene type compounds containing them as ligand
申请人:HONSHU CHEMICAL INDUSTRY CO. LTD.
公开号:EP1122229A1
公开(公告)日:2001-08-08
A process for producing a crosslink-cyclized cyclopentadiene, comprising the steps of reacting a cyclopentenone with an alkali metal hydride to thereby reduce the cyclopentenone (reduction step A) into a cyclopentenol; and reacting the cyclopentenol with a dehydrating agent to thereby dehydrate the cyclopentenol (dehydration step B) into a crosslink-cyclized cyclopentadiene of the general formula (III):
wherein each of R1 and R2 independently represents a hydrogen atom or a linear or branched saturated alkyl group having 1 to 6 carbon atoms, n is an integer of 3 to 10, and the broken line in the 5-membered ring denotes that the 5-membered ring has two double bonds.