Reducing agent

摘要

In Example 8, beta-methylstyrene and allylbenzene are made by reducing cinnamaldehyde at 138-145 DEG C. with Me3N/formic acid adduct, formic acid, Cu2Cl2 and Pd/C. The allylbenzene is stated to be formed from the methylstyrene in working up the reaction mixture by boiling with powdered K2CO3. In Example 7, deep block dyes of unknown constitution are made by reducing chloranil or 1,4 - benzoquinone with Me3N/formic acid adduct, free formic acid being continuously added. The product from chloranil is stated to be practically Cl-free.ALSO:In Example 5, high molecular weight copolymers of trioxane with 1,3-dioxolan or oxthiolan are thermally stabilized by reduction with pyridine/formic acid. In Example 10, a rubber-like thermoplastic material containing elementary S is obtained by reducing polybutadiene sulphone with formic acid + Me3N/formic acid adduct. A similar reduction is carried out on polyethylene sulphone.ALSO:Adducts or salts of formic acid with tertiary amines are used to reduce inorganic compounds, not more than 20 wt. per cent of water being present, based on the compound being reduced. There may be thus obtained S from SO2 (see Example 11); NH3 or NH2OH from HNO2, its salts or esters; Ag from AgNO3; Cu via Cu+ from Cu++; and V, As, Mn, Pb, Cr, Bi and Se in lower valency states from their ions.ALSO:Adducts or salts of formic acid with tertiary amines are used to reduce organic compounds (other than a tertiary amine forming the reducing agent), not more than 20 wt. per cent of water (based on the compound to be reduced) being present. There are thus obtained, in examples, trichloroethanol from chloral hydrate or alcoholate; methyl formate from polyoxymethylene; p-nitrobenzyl formate (hydrolysed to the alcohol with aq. K2CO3) from p-nitrobenzaldehyde; cinnamyl and dihydrocinnamyl formates from cinnamaldehyde; formanilide from nitrobenzene. In the latter two reductions, Cu2Cl2 and Pd/C are used in addition to the formic acid adduct.ALSO:Cu2Cl2 and Pd/C are used together, in presence of Me3N/formic acid adduct and free formic acid, to effect various reduction reactions. In Example 12, a catalyst comprising finely-divided Cu mixed with the formates of bivalent Mn, Pb and Fe, and trivalent V and Cr, is prepared by reducing with Me3N/formic acid adduct and free formic acid, a mixture of Cu2Cl2, CuSO4, MnO2, PbO2, CrO3, NH4VO3 and FeCl3.