Patent GB-707598-A (GB)
Title: Improvements in or relating to triphenylols
IPC: C07C37/11
Filed: 1951-08-22
Abstract: Phenol-formaldehyde resins containing more than 50 per cent. of a triphenylol of the general formula <FORM:0707598/IV(a)/1> are prepared by condensing at least 1.8 mols of phenol with a mol of formaldehyde at a pH of between 3 and 8, preferably on the presence of zinc, magnesium or alumium ions as a catalyst, distilling off unreacted phenol and diphenylol methane and further distilling at 1 mm. of pressure or less to obtain a distillate of containing the triphenylols.  Other methods of preparation are also described (see Group IV (b)).  Heat hardened resins are also prepared by reacting a triphenylol of the above general formula with hexamethylene-tetramine or formaldehyde.  In examples triphenylols comprising 2:4-bis-(2-hydroxy-benzyl)-phenol; 2:4-bis-(4-hydroxy benzyl)-phenol; 2:6 - bis (2 - hydroxybenzyl) - phenol; 2:6-bis-(4-hydroxybenzyl)-phenol; 2-(2-hydroxybenzyl)-4-(4-hydroxybenzyl)-phenol; 2 - (4 - hydroxybenzyl) - 4 - (2 - hydroxybenzyl phenol and 2 - (2 - hydroxy benzyl) - 6 - (4 - hydroxybenzyl)-phenol and mixtures thereof are heated with hexamethylene tetramine and with formaldehyde to give heat hardened resins and a phenol-formaldehyde condensation product is distilled at 250 DEG C. at 1 mm. pressure to give a distillate consisting mainly of triphenylols, which is heated with hexamethylene tetramine to form a heat hardened resin.  Polyether resins are obtained by reacting a triphenylol of the above general formula with dichloroethane.ALSO:The invention comprises triphenylols of the formula <FORM:0707598/IV (b)/1> namely 2 : 4 - bis - (2 - hydroxybenzyl) phenol I; 2 : 4 - bis - (4 - hydroxybenzyl) phenol II; 2 : 6 - bis - (2 - hydroxybenzyl) phenol III; 2 : 6 - bis - (4 - hydroxybenzyl) phenol IV; 2-(2 - hydroxybenzyl) - 4 - (4 - hydroxybenzyl) phenol V; 2 - (4 - hydroxybenzyl) - 4 - (2-hydroxybenzyl) phenol VI; and 2 - (2 - hydroxybenzyl) - 6 - (4 - hydroxybenzyl) phenol VII and their preparation by condensing a hydroxy - hydroxy1 - diphenyl methane with an equimolar amount of monomethylol phenol, or by reacting a monomethylol diphenylol methane with phenol or by reacting a dimethylol phenol with at least two mols. of phenol. These condensations are preferably carried out in the presence of zinc, magnesium or aluminium ions as a catalyst, but other catalysts such as hydrochloric acid, ammonia, formic acid, boric acid and acetic acid may also be used.  The methylol derivatives of phenols, used as starting materials may be prepared by reacting the phenol with formaldehyde if desired in situ.  A phenol formaldehyde novalak resin containing a major proportion of the above compounds is prepared by reacting formaldehyde with an excess of phenol (see Group IV (a)).  In examples (1) 4 : 41 dihydroxydiphenylmethane is reacted with 4-hydroxybenzyl alcohol to give II; (2) phenol is condensed with paraform in acid solution and isomer II is separated from the product; (3) 2 : 21-dihydroxydiphenylmethane is reacted with saligenin to give III; (4), (11) and (12) phenol and formaldehyde are condensed at pH 5-6 and III is separated from the product; (5) 2 : 6-dimethylol phenol and phenol are reacted to give III; (6) 4 : 41-dihydroxydiphenylmethane is reacted with saligenin to give V; (7) 2 : 4-dimethylol phenol is reacted with phenol or 2 : 4-dihydroxydiphenylmethane is reacted with 2-hydroxybenzyl alcohol to give I, this compound may also be isolated from the reaction products of example (3); (8) 2 : 6-dimethylol phenol is heated with phenol to give IV, which is also obtained together with isomer VI by reaction of 2 : 4 - dihydroxy diphenylmethane with 4 hydroxybenzyl alcohol; and (10) 2 : 21 - dihydroxydiphenylmethane is heated with 4-hydroxybenzyl alcohol and isomer VII is isolated from the products. Other examples are given.