Methyl hydride

Methyl-gallusathersaure, /. 0-methylgallic acid, methyl ether of gallic acid, -grtin, n. methyl green, -hydriir, n. methyl hydride, methane. 

The observation of stable Pt(IV) alkyl hydrides upon protonation of Pt(II) alkyls has provided support for the idea that the methane which had been observed in earlier studies (89-92) of protonation of Pt(II) methyls could be produced via a reductive elimination reaction from Pt(IV). An extensive study of protonation of Pt(II) methyl complexes was carried out in 1996 (56) and an excellent summary of these results appeared in a recent review article (14). Strong evidence was presented to support the involvement of both Pt(IV) methyl hydrides and Pt(II) cr-methane complexes as intermediates in the rapid protonolysis reactions of Pt(II) methyls to generate methane. The principle of microscopic... 

Section III.C A Hydrido(methyl)carbene Complex of Platinum(IV) (223) and Methyl(hydrido)platinum(IV) Complexes with Flexible Tridentate Nitrogen-Donor Ligands (224) are structurally related to the system shown in Scheme 13 and give additional information on how steric and electronic factors influence the stability of platinum(IV) methyl hydrides. 

Methylic hydride, or marsh gas, is produced during putre> faction, and by the distillatiou of potaesio acetate with excess of potiUKuo hydrate,... 

Similar octahedral facial silyl methyl hydride complexes of the type IrL3H(SiR3)Me have been shown to induce competitive C—H/Si—C reductive elimination depending on the electronic properties of the silyl ligand, thus affording a novel example of a metallation of silyl ligands or the metallation of the sp3C—H bond of the ethyl moiety when R = OEt. For the complex with R = Et, mixtures of different complexes are formed by the thermolysis with benzene (Scheme 32)198,199. 

However, the complex is thermally unstable, and rapidly decomposes as its solution is warmed to RT. As measured by GC-MS, the volatile products of the reaction contain Et3SiCl and (Et3Si)20 as two major components, characteristic of heterolytic cleavage of the r 2-Si H bond. The (Et3Si)20 was presumably formed by the reaction of Si Et, with adventitious H20, and Et3SiCl was formed by attack of SiEt, on CD2C12 solvent. Pd black also forms, possibly due to methane elimination from an unobserved Pd methyl hydride complex and instability of the resulting Pd(0) species. 

A major question is whether heterolytic cleavage of the H3C-H bond occurs as depicted in Scheme 10 (maintaining the Ptn state) or whether oxidative addition to a PtIV methyl hydride complex takes place. In such systems transfer of protons would be expected to be very facile because of the extremely high mobility of H +, and even a short-lived, very weak a complex could be a key intermediate. The C-H bond is likely to be polarized towards Cs H5+ on such highly electrophilic cationic metal complexes, where H+ can very rapidly split off and transfer to either a cis ligand or the anion as soon as the... 

Figure 1. FTIR spectra of the DVB-St (a) and DVB-MEDDE (b) copolymers without filler (1) and filled with methyl- 2,2 ) or methyl,hydride-containing fumed silicas (3). The spectrum marked as 2 was obtained at significant dilution of a sample with KBr.

After filling of the DVB-DMN copolymer with methyl-containing silica, a band at 1144 cm1 was detected in the spectrum indicating increased crystallinity. Crystallinity was not detected in the spectrum of copolymer filled with methyl,hydride-containing silica. 

Figure 3. AFM micrographs of DMN-DVB copolymers without filler (a) and filled with methyl-(b) or methyl,hydride-containing fumed silicas (c).

After filling with methyl,hydride-containing silica (Figure 4, 2), these chemical shifts were detected but with lower intensity. Resonances were... 

Figure 4. C 1FI [ DEPT NMR spectra for DVB and St monomers and 13C CP/MAS NMR spectra for DVB-St copolymers filled with methyl- (/) and methyl,hydride-containing silicas (2).

After filling of DMGE-DVB copolymer with methyl,hydride-containing silica, the appearance of a resonance at 39.9 ppm indicated the formation of Si-C bonds between the silica surface and DMGE (Figure 5). Comparison with the chemical shift of carbon in the ester carbonyl... 

Figure 6. C II jDF.PT NMR spectra for MEDDE monomers and 13C CP/MAS NMR spectra for MEDDE-DVB copolymer filled with methyl,hydride-containing silica.

The character of the filler effect depends on the affinity of the silica surface for the copolymer, and the rigidity of macromolecules. For MEDDE-DVB and DMGE-DYB copolymers, the introduction of both methyl-, and methyl,hydride-containing silicas results in the formation of amorphous structures. A greater degree of disorder was detected in the presence of silicon hydride groups on the filler surface. 

Filling of DYB-St copolymer with methyl,hydride-containing silica results in material cross-linking, and an increase in crystallinity was observed. For the DMN-DVB copolymer, an increase in crystallinity was significant with methyl-containing silica. The presence of silicon hydride groups on the filler surface promotes material cross-linking and the formation of an amorphous structure. 

L = PMes) to allow the use of rare, gaseous and solid alkanes. These studies show that methane gives the methyl hydride, cubane the cubyl hydride (without C—C bond breaking) and adamantane the secondary adamiuityl hydride. 

SYNS FIRE DAiMP MARSH GAS METHANE, compressed (UN 1971) QDOT) METHANE, refrigerated liquid (crj ogenic liquid) (UN 1972) OT) METHYL HYDRIDE NATURAL GAS, compressed (with high methane content) (UN 1971) (DOT) NATURAL GAS, refrigerated liquid (cryogenic liquid) (with high methane content) (UN 1972) (DOT)... 

METHYL HYDRIDE see MDQ750 A -6-a-METHYLHYDROCORTISONE see MOR300 METHYL HYDROXIDE see MGB150... 

Synonyms Natural gas Fire damp Marsh gas Methane (compressed, UN1971, DOT) Methane (refrigerated liquid, UN1972, DOT) Methyl hydride... 

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