Lead formate

Formic Acid, HCOOH (in aqueous solution), and Lead Formate, (HCOO)2Pb. 

To obtain lead formate, add about 100 ml. of water to the distillate and then stir powdered lead carbonate into the gently heated solution until no further effervescence of carbon dioxide occurs. Then boil the mixture vigorously and filter at the pump. 

A considerable amount of the formic acid, however, still remains behind in the distilling-flask as the unhydrolysed monoformate. Therefore, if time allows, dilute the residue in the flask with about an equal volume of water, and then steam-distil, the monoformate ester being thus completely hydrolysed and the formic acid then driven over in the steam. Collect about 400 ml. of distillate. Add this distillate to that obtained by direct heating of the reaction mixture and then treat with lead carbonate as described above. Total yield of lead formate is now about 40 g. 

Lead formate is only slightly soluble in cold water, and insoluble in hot absolute ethanol it can therefore be readily distinguished from lead acetate or sugar of lead because, quite apart from chemical tests, the acetate is readily soluble in cold water and moderately soluble in ethanol. 

Lead formate separates from aqueous solution without water of crystallisation. It can therefore be used for the preparation of anhydrous formic acid. For this purpose, the powdered lead formate is placed in the inner tube of an ordinary jacketed cond ser, and there held loosely in position by plugs of glass-wool. The condenser is then clamped in an oblique position and the lower end fitted into a receiver closed with a calcium chloride tube. A current of dry hydrogen sulphide is passed down the inner tube of the condenser, whilst steam is passed through the jacket. The formic acid which is liberated... 

HCOO)2Pb + H2S 2HCOOH + PbS. collects in the receiver, and is th i purified from dissolved hydrogen sulphide by redistillation over a further quantity of lead formate. 

Renciio/is Foi the follow-ing tests use a neutral solution pared as follows —Boil a little lead formate with a soltitioii ol... 

Picric acid Lead Formation of lead salt sensitive to shock and friction... 

PKC6H2N307)2.3Pb(0H)2.3Pb(C2Hs02)2, 277°C Monobasic lead picrate-lead formate, Pb(C6H2N307)2.Pb(OH) jjPbttiCO.jJa, 258°C Dibasic lead picrate-lead formate, Pb(C6H2N307)2.2Pb(0H)2.2Pb(HC02)2, 277°C... 

T riba sic lead picrate-lead formate, Pb(C6H2N807)2.3Pb(0H)3.3Pb(HCO2)2,247°C... 

Pb(CH02)2 (c). Berthelot9 measured the heat of solution of lead formate. 

Two approaches to bring in a monocyclic aziridine have been reported they differ largely in which bond is formed first. As shown in Scheme 61, Rapoport and co-workers create the G(ll)-N bond first to form 314 <2003JOC130>. Treatment of 314 with benzenesulfonyl anhydride (BS2O) leads formation of the aziridine 315 through an initial di-phenysulfonylation of the N-H and hydroxide followed by an intramolecular alkylation of the A-(9-phenylfluoren-9-yl)... 

Diformate,— This is deposited in prisms from alcohol, winch partially sublime without decomposition. Its crystals resemble those from calcium, barium, and lead formates. 

EINECS 212-371-8 Formic xid, iead(2+) salt Lead diformate Lead formate Lead formate (Pb(HC02)2) Lead(2+) formate NSC 112233 Ledfo. Solid d = 4.63 dec. at 190° soluble in water insoluble in alcohol. Mechema Chemicals Ltd. 

Hofmann (53) found an appreciable amount of formaldehyde (about 25%) and small amounts of methyl formate during the decomposition of zinc formate. Lithium formate produced acetone (about 20%) from lead formate, formaldehyde and methyl alcohol were formed. Pichler (127) found that during the decomposition of calcium formate, oxalate was formed. In general it appeared that the nature and the amount of the organic by-products depended largely on the reaction conditions [Hofmann (53)]. 

Solubility op Lead Formate in Aqueous Solutions of Barium... 

The kinetics of oxidation of the formate anion by aqueous bromine have been investigated by a potentiometric method the product of the reaction is COg. The influence of y-irradiation on the kinetics of thermal decomposition of lead formate has been assessed. The decomposition of the salt ... 

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