Carbonyl hydrides preparation

Chromium-based reagent systems, for pinacol coupling, 11, 63 Chromium carbenes, in ene-yne metathesis, 11, 272 Chromium carbonyl compounds with bridging hydrides, 5, 206 computational studies and spectroscopy, 5, 203 experimentally determined structures, 5, 204 nitro and nitroso compounds, 5, 205 silatropic migrations, 5, 249 with very weakly bonded ligands, 5, 205 Chromium carbonyl hydrides, preparation and characteristics,... 

Iron carbonyl hydrides, preparation and properties, 6, 7 Iron cations, acyclic (rj5-pentadienyl) Fe, 6, 153-154 Iron clusters... 

CoHjRuICOIjH/ Arene carbonyl hydrides prepared from Yellow (62a) 20.92 (62a) ... 

Sodium salts of carbonyl hydrides prepared in ethereal media, synthesis 53... 

SODroM SALTS OF CARBONYL HYDRIDES PREPARED IN ETHEREAL MEDIA... 

A few metal carbonyl hydrides can be prepared by direct reaction of the metal with CO and H2, with the following being a typical reaction ... 

Many of the methods used for the preparation of mononuclear hydrides may be applied to the polynuclear systems. Base attack on metal carbonyls, which furnished one of the first methods for the production of carbonyl hydride species, is applicable to a wide range of carbonyls. Borohydride reduction leads to a variety of products, depending upon the reaction conditions, Os3(CO)12 reacting with NaBH in di-oxane under reflux to give, after 4 hours, a mixture of the anions [H30s4(C0)12] and [H2Os4(CO)i2]2 (79). The related reaction in tetra-hydrofuran for 1 hour yields the anion [HOs3(CO)n]- as the main product with minor amounts of the two tetranuclear anions. 

Similar to chemical vapor deposition, reactants or precursors for chemical vapor synthesis are volatile metal-organics, carbonyls, hydrides, chlorides, etc. delivered to the hot-wall reactor as a vapor. A typical laboratory reactor consists of a precursor delivery system, a reaction zone, a particle collector, and a pumping system. Modification of the precursor delivery system and the reaction zone allows synthesis of pure oxide, doped oxide, or multi-component nanoparticles. For example, copper nanoparticles can be prepared from copper acetylacetone complexes [70], while europium doped yttiria can be obtained from their organometallic precursors [71]. 

The compound may be prepared in a similar way from cobalt(II) iodide. Also, it may be prepared by thermal decomposition of cobalt carbonyl hydride ... 

Submitted by MICHAEL 1. BRUCE and MICHAEL L. WILLIAMS Checked by GUY LAVIGNE and TH RESE ARLIGUIEt This tetranuclear ruthenium carbonyl hydride was described on several occasions,5 but early preparations were usually contaminated with Ru3(CO)12, giving rise to suggestions of the existence of two isomeric forms. The situation was clarified by the work of Kaesz and coworkers,6 who discovered the direct route from Ru3(CO)12 and hydrogen, which is described below. The compound is often obtained from reactions between Ru3(CO)12 and substrates containing hydrogen (hydrocarbons, ethers, alcohols, water, etc.) and by acidification of anionic ruthenium cluster carbonyls.7... 

Osmium-Carbonyl-Hydride Clusters and Related Ruthenium Complexes. Our investigation of these species began with a study of the species (/i2-H)(H)Os3(CO)n, prepared from Os3(CO)i2 via the unsaturated species (M2-H)20s3(CO)io (33) (see Reaction 1). 

The Th4H15 samples were prepared by Cameron Satterthwaite and coworkers (1,2) and consisted of two polycrystalline samples that were determined to be within 1% of the stoichiometric composition, Tn4Hi5 o.i5 The samples differed primarily in the pressure and temperature used in their synthesis. The sample hydrided under lower pressure ana temperature conditions (1 atm of H2 and a temperature cycle initiating at 800° K and dropping to 450° K before removing the H2) is labeled the LP sample, and the one hydrided under higher pressure and temperature (1100° K ana 10,000 psi of H2) is labeled HP. The sample preparation and characterization of this stoichiometric compound is apparently critical since the results of the present study differ significantly from the previous NMR studies (12,13,14), and some difference was detected between the LP and HP samples themselves. The carbonyl hydride samples were furnished kindly by John R. Shapley (20). 

Scheme 9. Preparation of osmium carbonyl/hydride/phosphine or arsine synthetic intermediates via the reactions of coordinated ligands.

In the classical oxo process the catalyst cohalt carbonyl is formed in situ by introducing divalent cobalt into the reactor. High temperature is required for this catalyst formation that gives a mixture of aldehydes and alcohols containing only 60-70% of linear product. A new BASF process using cobalt carbonyl hydride shows improved selectivity and efficient catalyst recovery. The catalyst is prepared by passing an aqueous solution of cobalt salt over a promoter and extracting the catalyst from the water phase with olefin. 

Fluorous organometallic chemistry, examples, 1, 842 Fluorous solubles, in organometallic synthesis, 1, 81 Fluorous solvents, for hydroformylations, 11, 450 Fluorous tin hydrides, preparation and applications, 9, 346 Fluorovinyl groups, vinylic C-F bond activation, 1, 753 Fluoro vinyltitanocenes, synthesis, 4, 546 g tfZ-Fluorovinyltributylstannane, in carbonylative cross-coupling, 11,413... 

We later prepared the more stable phosphine-substituted mononuclear carbonyl hydrides such as FICo(CO)4 nLn and FHVfn(CO)5 L n= 1 and 2 ... 

The mercury compounds HgFe(CO)4 and Fe(CO)4(HgX)2 (X = C1, Br, I), which were the first representatives of non-ionic metal derivatives of iron carbonyl hydrides, were discovered by Hock and Stuhlmann (V, 36). During investigations into the preparation of cobalt carbonyls from cobalt halides under CO pressure, in the presence of another metal as a halogen acceptor, we discovered the mixed metal carbonyls M[Co(CO)4]2 (M = Zn, Cd, Hg, Sn) and M[Co(CO)4]3 (M = In, Tl) (44), e.g.,... 

Other monomeric carbonyl hydrides whose structures have been investigated are the cis and trans isomers of [H2Re(CO)4]- 49,5°). In neither case have the hydride ligand s been directly located. Trans-[H2 Re(C0)4 ] was prepared in low yield from the pyrolysis of c/s-[H2 Re(CO)4 ], and was isolated as crystals of an unusual mixed salt [NEt4]2[Re4(CO)I6]2 [NEt4]+[H2Re(CO)4] 5°) (Fig. 8). 

The chemistry of the metal carbonyl hydrides and metal carbonylates remained the principal research topic for Hieber until the 1960s. He mentioned in his account [25], that it was a particular pleasure for him that in his laboratory the first hydrido carbonyl complexes of the manganese group, HMn(CO)5 and HRe(CO)5, were prepared by careful addition of concentrated phosphoric acid to solid samples of the sodium salts of the [M(CO)5] anions, giving the highly volatile hydrido derivatives in nearly quantitative yield [45, 46]. In contrast to HCo(CO)4 and its rhodium and iridium analogues, the pentacarbonyl hydrido compounds of manganese and rhenium are thermally remarkably stable, and in... 

In situ IR and NMR spectra showed that, indeed, the assembled diphosphine coordinates preferentially in the bis-equatorial, wide-bite-angle fashion to the penta-coordinated rhodium carbonyl hydride. Both homo- and heterocombinations of monophosphine ligands can be formed in situ by mixing the components several heterocombinations perform better as catalysts than the respective homocombinations. However, in contrast to the catalysts prepared by Takacs, the present complexes do not equilibrate to afford solely the heterocombination. 

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