With silver carbonate

Coesite. Coesite, the second most dense (3.01 g/cm ) phase of silica, was first prepared ia the laboratory by heating a mixture of sodium metasibcate and diammonium hydrogen phosphate or another mineraliser at 500—800°C and 1.5—3.5 GPa (14,800—34,540 atm). Coesite has also been prepared by oxidation of silicon with silver carbonate under pressure (67). The stmcture is monoclinic = 717 pm, Cg = 1.238 pm, and 7 = 120°. 

Concomitant protection of the amino group and the cis-hydroxyl group of the diol 342 was realized by treatment with formaldehyde to afford the oxazolidine 345, oxidation of which with silver carbonate on Celite gave the... 

Hepta-0-acetyl-(2-hydroxygentiobial) gave with chlorine a mixture of non-crystalline dichlorides which, on treatment with silver carbonate, formed an acetylated osone derivative. With pyridine and acetic anhydride, this was converted into an acetate of 6-0-/3-D-glucosylkojic acid.140... 

In contrast to the oxidation of acyclic polyhydric alcohols in benzene,508 treatment of 1,2-O-isopropylidene-a-D-glucofuranose with silver carbonate-on-Celite in boiling methanol led to selective oxidation of the primary hydroxyl group, with the formation of the al-duronic acid derivative in 68% yield.517... 

The cycloaddition of nitrilimines toward furo[3,4-c]thieno[2,3-r7]-pyrazoles has been investigated as a function of the electron-withdrawing or electron-donating character of the substituents attached to the aromatic rings <2000H(53)917>. For instance, nitrilimine 459, obtained in situ from hydrazonoyl chloride 458, by base treatment with silver carbonate in dioxane, when reacted with 460, gives a mixture of compounds 461 and 63 (Scheme 53) <2000H(53)917>. 

Chaplin used methanolysis for the analysis of carbohydrates in glycoproteins. His method was a variation of the foregoing procedures, with an improvement of using tert-hvAyX alcohol to remove hydrogen chloride by coevaporation, instead of prolonged trituration with silver carbonate. His method is useful for samples containing uronic acids and lipids. Mononen studied methanolysis, followed by deamination and reduction with borohydride, for determination of the monosaccharide constituents of glycoconjugates. This method was applied to a lipid-free, protein fraction of rat brain. 

Zempl6n and Kiss, in the case of pentaacetyl-D-glucononitrile, removed the acetyl groups by heating the compound with sulfuric acid in ethanol, a procedure that left the nitrile almost intact. This group was subsequently eliminated with silver carbonate and D-arabinose was isolated as the diphenylhydrazone. This procedure was applied to other nitriles by Deulofeu and coworkers. ... 

Deulofeu also degraded tetraacetyl-D-arabononitrile with sodium methoxide or by hydrolysis of the acetyl groups with sulfuric acid and separation of the nitrile group with silver carbonate. D-Erythrose was characterized as the phenylosazone. 

By employing aqua ammonia, the yield of D-lyxose diacetamide from the nitrile was improved to 72%. Degradation of the nitrile with sodium methoxide yielded 30% of D-lyxose, isolated as the p-bromo-phenylhydrazone. Treatment with silver carbonate subsequent to hydrolysis of the acetyl groups resulted in a 22% yield. 

A branched-chain iodo sugar derivative, l,5-anhydro-4,6-0-benzyl-idene-2,3-dideoxy-3-C-(iodomethyl)-D-rifoo-hex-l-enitol [4,6-O-ben-zylidene-3-deoxy-3-C-(iodomethyl)-D-allal] (200), is one of the products formed on treatment of methyl 4,6-0-benzylidene-2,3-dideoxy-a-D-en/thro-hex-2-enopyranoside (77) with the Simmons-Smith reagent (diiodomethane and zinc-copper couple).123,212 Compound 200 displays high solvolytic reactivity, an observation that has been rationalized by supposing the formation of the highly stabilized carbonium ion213 (201). Thus, under conditions wherein methyl 2,3,4-tri-0-acetyl-6-deoxy-6-iodo-a-D-glucopyranoside required more than 24 hours to react appreciably with an excess of silver nitrate in 50% aqueous p-dioxane buffered with silver carbonate, the iodide 200 was hydrolyzed completely in less than 1 minute the product of hydrolysis of 200 is the cyclopropyl aldehyde 202. Methanolysis of... 

For instance, on adding mercuric oxide, the reaction proceeds 2C12 + H20 + HgO = HgCl2 2HC10, and with silver carbonate 2C12 + H20 ... 

Chloro-pentammino-chromic Sulphate, [Cr(N I3)5Cl]S04.2H20, is prepared by treating the chloride with silver carbonate, removing the precipitated silver chloride and cautiously adding to the liquid dilute sulphuric acid a little silver chloride is thereby precipitated, it is removed by filtration, and the sulphate is precipitated from the filtrate by means of alcohol in carmine-red prisms. It is fairly soluble in water, and loses water if left over sulphuric acid or on heating to 100° C. 

Hexammino-cobaltie Carbonate, [Co(NH3)8]2(C03)3.7H20, is likewise prepared from the chloride by treating an aqueous solution with silver carbonate. It crystallises from hot water in yellowish-brown rhombic crystals containing seven molecules of water. The water of hydration is lost on exposure to dry air and the compound becomes opaque and powdery. 

S. Morgenlie, Isopropylidene derivatives of a-D-galatofiiranose, Acta Chem. Scand. 27 3609 (1973) S. Morgenlie, Oxidation of carbohydrate derivatives with silver carbonate on celite. X. Identification of three mono-O-isopropylidene derivatives of D-galactose, Acta Chan. Scand B 29 367 (1975) S. Morgenlie, Reaction of some aldoses with anhydrous cupric sulphate-acetone, Carbokydr. Res. 41 77 (1975). 

In Scheme 16 the reaction between Pt02(PPh3)2 and C02 was shown to give the peroxycarbonate complex Pt(03C0)(PPh3)2. If this reaction is carried out in the presence of free triphenylphosphine, or if the synthesis is achieved directly from Pt(PPh3)3 (equation 466), the carbonato complex (171) is formed.1618 Alternatively carbonato complexes can be prepared from the dihalo complexes by treatment with silver carbonate (equation 467).1619,1620 These complexes are air-stable but liberate C02 with added protonic acids. 

Nitrile imines can cyclize to 1,1-cycloadducts if the dipole-dipolarophile parallel plane approach is unfavorable. Thus, cyclopropanes (175a-b) were independently obtained on short-term reaction of the chlorohydrazone precursors with silver carbonate (Scheme 55).93 Longer reaction times afforded a 3 1 b a ratio from either precursor the products were shown to equilibrate. Heating of cyclopropanes (175a-b) afforded a benzodiazepine. 

The available experimental data4 are consistent with the following mechanism for the oxidation of alcohols with silver carbonate on Celite ... 

A corollary of this selectivity is the very easy transformation of diols into lactones with silver carbonate on Celite .16 During the oxidation of a diol with Fetizon s reagent, as soon as an intermediate hydroxyaldehyde is able to equilibrate with a certain proportion of hemiacetal—even if present... 

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