the reactor to a temperature between about 70 u00b0 c and about 80 u00b0 c and holding the pressure and temperature for about 30 minutes the reactor contents were then cooled and the vacuum dropped by the addition of nitrogen the product was about 450 grams of tris n hexoxymethanamine a nitrogen purged glass reaction flask was charged with 226 2 grams of monochlorobenzene 39 grams of water and 226 2 grams of neopentyl glycol during a period of about 3 hours 298 8 grams of phosphorus trichloride were added during the first one third of the addition the reaction is exothermic and the batch was cooled to maintain the temperature between about 40 u00b0 c and about 50 u00b0 c after about one third of the phosphorus trichloride was added hydrogen chloride gas evolved at a substantial rate and external cooling was no longer necessary as the evolution of hydrogen chloride gas is endothermic the hydrogen chloride gas was sent to a water scrubber the reactor contents were kept at a temperature between about 40 u00b0 c and about 50 u00b0 c by heating the reactor and the addition of the phosphorus trichloride was continued at a rate that prevented foaming after the addition of the phosphorus trichloride was completed the temperature of the batch was raised to about 110 u00b0 c at a rate slow enough to prevent excessive foaming as additional hydrogen chloride gas was eliminated the batch was held at about 110 u00b0 c.