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Title: Metal-assisted hydroformylation on a SiO sub 2 -attached Rh dimer. In situ EXAFS and FT-IR observations of the dynamic behaviors of the dimer site

Abstract

trans-(Rh(C{sub 5}Me{sub 5})(CH{sub 3})){sub 2}({mu}-CH{sub 2}){sub 2} was supported on the SiO{sub 2} surface by the reaction with OH groups of SiO{sub 2} at 313 K, followed by evacuation at 373 K. In this attaching reaction, the Rh dimer complexes were bound to the SiO{sub 2} surface through Rh-O(surface) bonds, losing one CH{sub 3} ligand and one C{sub 5}Me{sub 5} ligand per Rh dimer. The attached Rh dimers were found to be more active and selective than a conventionally prepared Rh/SiO{sub 2} catalyst. The structure change of the Rh dimer sites in each reaction step for catalytic hydroformylation was followed by means of in-situ FT-IR and in situ EXAFS techniques. The Rh-Rh bond in the attached Rh dimers (Rh-Rh = 0.262 nm) was cleaved by CO adsorption to form monomer pairs (Rh(C{sub 2}H{sub 5})(CO){sub 2}(O-Si) + Rh(C{sub 5}Me{sub 5})(O-Si)). Heating the monomer pairs to 423 K under vacuum resulted in CO insertion, with new peaks exhibited at 1,710 and 1,394 cm{sup {minus}1} due to the acyl ligand.

Authors:
; ;  [1];  [2];  [3]
  1. Univ. of Tokyo (Japan)
  2. National Chemical Lab. for Industry, Ibaraki (Japan)
  3. Inst. for Molecular Science, Aichi (Japan)
Publication Date:
OSTI Identifier:
5955451
Resource Type:
Journal Article
Journal Name:
Journal of the American Chemical Society; (United States)
Additional Journal Information:
Journal Volume: 112:25; Journal ID: ISSN 0002-7863
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ETHYLENE; ACYLATION; RHODIUM COMPLEXES; CATALYTIC EFFECTS; CATALYST SUPPORTS; CYCLOPENTADIENE; DIMERS; FORMATES; FOURIER TRANSFORM SPECTROMETERS; INFRARED SPECTRA; LIGANDS; MOLECULAR STRUCTURE; REACTION INTERMEDIATES; SILICON OXIDES; ALKENES; CARBOXYLIC ACID SALTS; CHALCOGENIDES; CHEMICAL REACTIONS; COMPLEXES; CYCLOALKENES; DIENES; HYDROCARBONS; MEASURING INSTRUMENTS; ORGANIC COMPOUNDS; OXIDES; OXYGEN COMPOUNDS; POLYENES; SILICON COMPOUNDS; SPECTRA; SPECTROMETERS; TRANSITION ELEMENT COMPLEXES; 400201* - Chemical & Physicochemical Properties

Citation Formats

Asakura, Kiyotaka, Kitamura-Bando, Kyoko, Iwasawa, Yasuhiro, Arakawa, Hironori, and Isobe, Kiyoshi. Metal-assisted hydroformylation on a SiO sub 2 -attached Rh dimer. In situ EXAFS and FT-IR observations of the dynamic behaviors of the dimer site. United States: N. p., 1990. Web. doi:10.1021/ja00181a010.
Asakura, Kiyotaka, Kitamura-Bando, Kyoko, Iwasawa, Yasuhiro, Arakawa, Hironori, & Isobe, Kiyoshi. Metal-assisted hydroformylation on a SiO sub 2 -attached Rh dimer. In situ EXAFS and FT-IR observations of the dynamic behaviors of the dimer site. United States. doi:10.1021/ja00181a010.
Asakura, Kiyotaka, Kitamura-Bando, Kyoko, Iwasawa, Yasuhiro, Arakawa, Hironori, and Isobe, Kiyoshi. Wed . "Metal-assisted hydroformylation on a SiO sub 2 -attached Rh dimer. In situ EXAFS and FT-IR observations of the dynamic behaviors of the dimer site". United States. doi:10.1021/ja00181a010.
@article{osti_5955451,
title = {Metal-assisted hydroformylation on a SiO sub 2 -attached Rh dimer. In situ EXAFS and FT-IR observations of the dynamic behaviors of the dimer site},
author = {Asakura, Kiyotaka and Kitamura-Bando, Kyoko and Iwasawa, Yasuhiro and Arakawa, Hironori and Isobe, Kiyoshi},
abstractNote = {trans-(Rh(C{sub 5}Me{sub 5})(CH{sub 3})){sub 2}({mu}-CH{sub 2}){sub 2} was supported on the SiO{sub 2} surface by the reaction with OH groups of SiO{sub 2} at 313 K, followed by evacuation at 373 K. In this attaching reaction, the Rh dimer complexes were bound to the SiO{sub 2} surface through Rh-O(surface) bonds, losing one CH{sub 3} ligand and one C{sub 5}Me{sub 5} ligand per Rh dimer. The attached Rh dimers were found to be more active and selective than a conventionally prepared Rh/SiO{sub 2} catalyst. The structure change of the Rh dimer sites in each reaction step for catalytic hydroformylation was followed by means of in-situ FT-IR and in situ EXAFS techniques. The Rh-Rh bond in the attached Rh dimers (Rh-Rh = 0.262 nm) was cleaved by CO adsorption to form monomer pairs (Rh(C{sub 2}H{sub 5})(CO){sub 2}(O-Si) + Rh(C{sub 5}Me{sub 5})(O-Si)). Heating the monomer pairs to 423 K under vacuum resulted in CO insertion, with new peaks exhibited at 1,710 and 1,394 cm{sup {minus}1} due to the acyl ligand.},
doi = {10.1021/ja00181a010},
journal = {Journal of the American Chemical Society; (United States)},
issn = {0002-7863},
number = ,
volume = 112:25,
place = {United States},
year = {1990},
month = {12}
}