Thermal solid-state diag-lat isomerisation studies of (η5-C5H4R)Re(CO)(L)Br2:: DSC and thermomicroscopy studies

被引：6

作者：

Cheng, L ^{[1
]}

Coville, NJ ^{[1
]}

机构：

[1] Univ Witwatersrand, Dept Chem, Ctr Appl Chem & Chem Technol, ZA-2050 Wits, Johannesburg, South Africa

来源：

THERMOCHIMICA ACTA | 1998年 / 319卷 / 1-2期

关键词：

DSC; microscopy; isomerisation; rhenium complexes; cyclopentadienyl;

D O I：

10.1016/S0040-6031(98)00365-7

中图分类号：

O414.1 [热力学];

学科分类号：

摘要：

The thermal solid-state diag-lat isomerisation of (eta(5)-C5H4R)Re(CO)(L)Br-2 (R=Me, tBu and SiMe3; L=CO, CNC6H3Me2, P(OMe)(3) and P(OPh)(3)) has been studied by DSC, and thermomicroscopy. In all instances, where isomerisation of (eta(5)-C5H4R)Re(CO)(L)Br-2 (1) was observed, the diagonal (trans) isomer converted to the lateral (cis) isomer in an exothermic reaction. The effects of heating rate and crystal size on the isomerisation reaction involving (1) (R=Me, L=CO) has been studied. Microscopic studies on 1, (R=Me, L=CO and P(OPh)(3); R=tBu, L=CNC6H3Me2) showed that the solid-state isomerisation reactions proceeded via a nuclear formation and growth mechanism.. Interestingly, no crystal cracking was observed when (1) (R=Me, L=P(OPh)(3)) underwent a thermal solid-state isomerisation reaction. (C) 1998 Elsevier Science B.V.

引用

页码：27 / 32

页数：6

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