16081-16-6Relevant articles and documents
Highly active chromium-based selective ethylene tri-/tetramerization catalysts supported by PNPO phosphazane ligands
Zhou, Yusheng,Wu, Hongfei,Xu, Sheng,Zhang, Xuejun,Shi, Min,Zhang, Jun
, p. 9545 - 9550 (2015/06/16)
Novel Cr(iii) catalysts supported by PNPO phosphazane ligands of the type Ph2PN(R)P(Ph)OAr have been prepared, all of which, upon activation with MMAO-3A, are highly active in ethylene tri-/tetramerization with considerable selectivity. The effect of ligand substitution on the catalytic performance has been examined. The Cr precatalyst supported by the PNPO phosphazane ligand with an N-cyclohexyl achieved high activity of 316.7 kg (g Cr h-1)-1 and a high total selectivity of 85.1% towards valuable 1-hexene (45.7%) and 1-octene (39.4%) using chlorobenzene as the solvent at 35 bar and 40 °C. In methylcyclohexane, the precatalyst supported by [Ph2PN(iPr)P(Ph)OPh] exhibited a higher 1-octene selectivity (54.0%) with a considerable activity of 73.3 kg (g Cr h-1)-1 at 35 bar and 40°C. With the fine-tuned ligand backbone, such a PNPO phosphazane-based catalyst system provides a mode for precise understanding of the impact of ligand variations on catalytic performance.
Aryloxymethyl derivatives of nitrogenous heterocyclic methanols and ethers thereof
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, (2008/06/13)
Novel heterocyclicmethanols are disclosed having the formula: STR1 wherein Z is pyrrolidinyl, piperidinyl, homopiperidinyl or pyridinyl; R1 is hydrogen, loweralkyl or carbethoxymethyl; R2 is hydrogen, loweralkyl, cycloalkyl, phenyl or phenyl-loweralkyl; R3 is 1 or 2-naphthalenyl, 2,3-dihydroinden-4 or 5-yl, phenyl or phenyl substituted by loweralkyl, loweralkoxy, halogen, trifluoromethyl, phenyl, methylenedioxy, nitro, amino, loweralkylamino, diloweralkylamino, loweracylamino; the 1-position of 2-pyrrolidinyl, 2-piperidinyl or 2-homopiperidinyl may be substituted by an R4 loweralkyl group, or R1 may form methylene or --CH2 -C(O)-bridges with R4 ; the pharmaceutically acceptable salts and diastereomers thereof, which compounds have antiarrhythmic and/or hypotensive activity in animals.
Process for the preparation of alkylthioalkanoate salts
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, (2008/06/13)
A process for the preparation of alkylthioalkanoate salts by reaction of an alkali metal alkylmercaptide with a lactone in the presence of an aprotic polar organic solvent. Preferably, the alkali metal mercaptide is prepared by reaction of an alkylmercaptan and an alkali metal phenate.