Methanol solvation

The water of hydration of these complexes can be replaced with other coordinating solvents. For example, the ethanol and methanol solvates were made by dissolving the hydrates in triethyl and trimethyl orthoformate, respectively (81,82). The acetic acid solvates are made by treating the hydrates with acetic anhydride (83). Conductivity and visible spectra, where appHcable, of the Co, Ni, Zn, and Cu fluoroborates in A/A/-dimethylacetamide (L) showed that all metal ions were present as the MLg cations (84). Solvated fluoroborate complexes of, Fe +, Co +, , Cu +, and in diethyl... 

However, the energy difference between N- and S-bonded thiocyanate is very small and is influenced by an interplay of several factors steric effects, solvent and the counter-ion in ionic complexes. To illustrate the last point, in complexes [Pd[Et2N(CH2)2NH(CH2)2NH2]NCS]+, the PFg salt is N-bonded, as it is in the unsolvated BPhg salt. However, though the acetone solvate of the tetraphenylborate is N-bonded, the methanol solvate is S-bonded [126],... 

C3aH60O30 C2H6OS 2 CH40 2 H20 Cyclomaltohexaose-dimethyl sulfoxide, methanol solvate, ACDMSM 43 354... 

The structure of the 1 1 methanol solvate of olanzapine has been reported, where pairs of olanzapine molecules form a centrosymmetric dimer by means of C—H—-7t interactions [66]. The solvent molecule was linked to the drug substance through O—H-N, N—H O, and C—interactions. In a new polymorph of the 1 1 dioxane solvatomorph of (+)-pinoresinol, the structure was stabilized by O—H O hydrogen bonds between the compound and the solvent [67], Two new polymorphs of 2-cyano-3-[4-(/Y,jV-diethylamino)-phenyl]prop-2-enethioamide and its acetonitrile solvatomorph have been characterized [68], Although crystallization of the title compound was conducted out of a number of solvents, only the acetonitrile solvatomorph could be formed. 

Fig. 19 The structure of 35 2Zn(II) OH (CF3SO3 )3 CH3OH as determined by X-ray diffraction. For clarity, the triflate counter ions and methanol solvate are not shown.

Few X-ray diffraction data are available for the organotin alkoxides. Trimethyltin methoxide in the crystal is a five-coordinate linear polymer 47,380 and both tin atoms in the methanol solvate, CH2(SnPh2OMe)2-MeOH, are five coordinate, one by intramolecular coordination, and the other by solvation 48.381 Dimethyltin dimethoxide 49,382 dimethyltin diphenoxide 50,383 and isopropyltin triisopropoxide 51384 are five-coordinate oxygen-bridged dimers. All these compounds are monomers in solution. 

Phenoxymethyl penicillin sulfoxide methanol solvate S J. Am. Chem. Soc. 1969,97, 1408... 

Reduction of p-oxo-bis[tetraphenylporphin iron(iii)] with sodium amalgam gives several products sequentially. The first reduction product is the radical-anion [(tpp)Fe ] , which has a spin state of - at 77 K and at 300 K. This is the first reported study of an Fe -porphyrin.Mossbauer data on a range of tetra-aryl-substituted iron-porphines and their p-oxo-bridged derivatives have been reported. A crystallographic study on bis(imidazole) otPy -tetraphenylporphinatoiron(iii) chloride-methanol solvate shows the [FeN ] core to be quasitetragonal. An n.m.r. study has been made of the related... 

The UV spectrum [Amax 243, 267 (sh), 292, 322 (sh), 335, 356, and 372 nm] of (+)-staurosporine (AM-2282) (295) was very similar to that of staurosporinone (293), indicating the presence of a similar indolo[2,3-fl]pyrrolo[3,4-c]carbazole framework. The IR spectrum indicated the presence of an NH band at v ax 3500 cm and an amide band at 1675 cm . The structure and relative stereochemistry of this isolate were established by X-ray crystallographic analysis of the methanol solvate (282,283). The structure 295, indicating the presence of an indolocarbazole subunit, wherein two... 

Examples of other organic materials prepared by mechanochemical procedures, for which stmcture determination has been carried out directly from powder XRD data, include a hydrate cocrystal of 5-methyl-2-pyridone and trimesic acid, which was prepared by grinding a methanol solvate cocrystal of the same components... 

The product isomerizes readily to the allenic sulfide, H2C=C CHSCH=CH2, or 1-propynyl sulfide, Cl CsCSCH CH-, under the influence of the alkenethiolate. For this reason, in versed-order addition is applied. The methanol solvates the alkenethiolate. thus rendering it less active in catalyzing the isomerization. 

On most occasions —H - interactions are not the only secondary bonds present in the supramolecular structure, but can afford higher dimensionality. In the ethanol and methanol solvates of the thiolate complex [Au(2-Hmba) P(o-Tol)3 [ (Hmba = 2-mercaptobenzoate) [34], two molecules are hydrogen bonded via two alcohol molecules about a center of inversion and centrosymmetrically related pairs aggregate via... 

In a more detailed study of the hydrogenation using [Ru(OAc)2(PPh3)2] (9) in benzene, methanol and methanol containing p-toluenesulfonic acid, the rate passed through a maximum at low acid concentration. This was attributed to the stepwise protonation of the acetate ligands, leading to cationic, methanol-solvated complexes (equation 17). 

The tagged resins are pooled into one large batch in a 2-liter peptide vessel, washed with methanol, and then left solvated. Separately, solid Ox-one is dissolved in water (to a final concentration of 0.4 M), sonicating for 5 min to aid in solvation. The aqueous Oxone solution (10 equivalents with respect to the nitro group loading of the resin) is added to the methanol-solvated resin and stirred/bubbled for 16 h at room temperature. The resulting resin 10 was then washed with water, MeOH/water (1 1), MeOH, MeOH/NMP, NMP, DCM, and ether, then dried in vacuo overnight prior to the next step. 

However, this equation does not yield acceptable results in the case of cryptates for instance (Faulkner et al., 2001) and must be used with extreme care. The corresponding equation for methanol solvation is (Beeby et al., 2002a) ... 

FIGURE 86. A molecule of the methanol-solvated (trz)2Pb(N03)2 adduct projected normal to the 2-axis. Reproduced by permission of the Australian Academy of Science and CSIRO from Reference 136... 

The photostimulated reactions of thiolate anions with 2-halo-2 -nitropropane derivatives yield both oc-nitrosulphides via an S l pathway and disulphides (equation 71a)282 284. In contrast with the case of the oxidative dimerisation products of the mono-enolates, the disulphides are formed via an ionic mechanism nucleophilic attack by the thiolate anion on the a-halogen and subsequent reaction of a second thiolate with the sulphenyl halide. As expected for such a process, disulphide formation is favoured (and thus a-nitrosulphide formation is disfavoured) the more nucleophilic the thiolate (i.e. derived from a less acidic thiol) and the easier the abstraction of the halo-substituent (i.e. I > Br > Cl). Use of the protic solvent methanol instead of the usual dipolar aprotic solvents for the reaction of equation 71a is detrimental to the yield of the S l substitution products exclusively disulphides are formed285 (equation 71b). Methanol solvation probably retards the dissociation of the radical anion intermediate in the SRN reaction, into radical and anion, and hence retards the chain reaction relative to the ionic reaction. The non-nucleophilic methylsulphinate ion gives only an S l reaction product with 2-bromo-2-nitropropane286. 

Aromoline and thalicberine have been isolated from Thalictrum lucidum,51 and berbamine and oxyacanthine from Berberis julianeae Schneid.52 The biosynthesis of bisbenzylisoquinoline alkaloids has been reviewed.53 An X-ray structure determination of ( + )-tubocurarine dibromide methanol solvate has been reported,54 and neuromuscular sensitivity to tubocurarine55 and the cardiovascular effects of the alkaloid56 have been further studied. Highly selective biological AT-demethylation of tetrandrine to iV(2 )-nortetrandrine by Streptomyces griseus has been described.29... 

An X-ray diffraction study72 of the methanol solvate of ervitsine has confirmed the structure and stereochemistry previously deduced. 

FIGURE 2. Molecular arrangement of methanol solvated lithium enolate of 1,3-cyclohexanedione (LiCHD)224... 

MCELOE Methyl /9-cellobioside methanol solvate (at -193 deg.C) (C H On, CH40). Ham JT, Williams DG (1970) Acta Crystallogr, Sect B 26 1373 MCYTIM10. Bis(l-methylcytosine) hydroiodide monohydrate (C5H7N30, C5H8N30+, I-, H20). 

There are also some examples of solvates (as opposed to hydrates) that have been reported to exhibit differing bioavailability. For instance, for implants of the methanol solvate of predisolone fert-butyl acetate the mean absorption rate was found to be 4.7 times that of the anhydrous form, which in turn was similar to the hemiacetone solvate (Ballard and Biles 1964). The same authors also reported that the mean absorption rate for all solvates of cortisol ferf-butyl acetate were significantly different from that of the anhydrous form. 

Trimesic acid 5-Methyl-2-pyridone Structure of a new cocrystal product generated by solid-state grinding of the methanol solvate cocrystal [52]... 

The noraporphine nandigerine, C18H17O4N, was isolated from Hernandia ovigera L. (Hernandiaceae). The base crystallized from methanol either as solvent free needles (mp 176°-177° [ajp - -248° in ethanol), or as plates of the methanol solvate, C]8Hi704N-CH30H (mp 99°-100°). The alkaloid hydrochloride salt melted at 245°-247° (decomp.) (33b). 

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