Poly:hydroxylated cpds. prepn. from formaldehyde - by condensing in presence of specified metallic cpd. and an alcohol

摘要

Polyhydroxylated cpds. of low mol. wt. possibly with hydroxyaldehydes and hydroxyketones, are prepd. by the condensation of formaldehyde hydrate in the presence of (I) 0.01-10 wt.% metallic cpd. catalysts and (II) 0-10 wt.% co-catalysts based on cpds. transformable into enediol. This condensation is carried out at 10-150 degrees C in the presence of (II). (I) is a sol. or insol. cpd. of the 1st to 8th sub-groups or 2nd to 4th principal groups of the periodic classification, possibly fixed to high molecular wt. supports. (II) is, at a level of >10 wt.% wrt HCHO, of >=1 mono- or polyalcohols of low mol. wt. and/or polyhydroxylated cpds. of high mol. wt. The reaction is terminated at a residual HCHO level of 0-10 wt.% by deactivation of the catalyst, the catalyst is eliminated and, if desired, the aldehyde and ketonic groups in the prod. are reduced to hydroxy gps. The polyhydroxylated cpds. can be used e.g. as cross-linkers in the prepn. of polyurethane resins, chain elongators, swelling agents, catalysts, to prepare nonionic surfactants, as humectants, anti-freezes, microorganism nutritive media, etc. The method gives 30-75 wt.% polyalcohols in the mixt., without decomposition products. Hydrogenation or redn. of the mixt. is simple and economical, because of the relatively low carbonyl gp. concn. High reproducibility of distribution can be obtd., e.g. mixts. contg. more than 80 wt.% >4C cpds. can be prepd. Colourless prods. are obtd. which can be hydrogenated directly.