R-A reaction of diethanolamine, diisopropanolamine, and N-(2-hydroxyprop yl)-ethanolamine as dialkanolamines and ammonia at around 200° in the presence of Raney nickel yielded 33% piperazine, 82% 2, 6-dimethylpiperazine, and 18% 2-methylpiperazine, respectively. Similarly, R-A reactions on N-alkyldiethanolamines (alkyl groups were methyl, ethyl, butyl and phenyl) showed greater hydrogen uptake with an increase of numbers of carbon atom in methyl, ethyl and butyl groups with the exception of the phenyl group. The reaction at 200°, besides recovering of raw material, only one or two of the hydroxyl groups in dialkknolamines were converted into amino groups and the formation of piperazine ring from alkyl groups composed of methyl, ethyl, butyl, and phenyl groups was 15%, 23%, 14%, and 16%, respectively. The R-A reaction of N-methyldiethanolamine and N-butyldiethanolamine at 250° decreased the amount of recovered raw material and the yield of products having higher boiling point than the reaction at 200° but the yield of products having lower boiliug point was increased. However, it was considered that there was no particular increase in yield of piperazine. The amount of hydrogen absorption was increased accordingly.
When 100cc of air containing acrolein and propylene was passed at the rate of 1cc/sec into the detector tube which contained hydroxyl amine hydrochlo ride and thymol blue on silica gel as detecting agent, acrolein discolored and coexisting propylene had no effect. Acrolein concentration (0.003-3.0%) was determined by measuring the length of discolored layer. Coexisting propylene was determined by means of the detector tube which contained sulphuric acid and chromic acid on silica gel (from orange to greenish black, measuring range 0.05-5.0%) or palladium sulphate and ammonium molybdate on silica gel (from pale yellow to blue, measuring range 0.01-1.0%). Acrolein detector and propylene detector were connected in series and 20cc of the mixed gas was sent at the feeding rate of 0.2cc/sec. Acrolein was absorbed by acrolein detector and eliminated. Propylene was determined with propylene detector by measuring the length of discolored layer. Acrolein detector absorbed a small portion of propylene which was removed by feeding pure air and sent to another propylene detector. Propylene concentration was determined by summing up the readings of two propylene detectors. Relative error of proposed method was within±10%.
Insoluble azo compounds were prepared from 2-methyl-5-chloroaniline (Fast Red KB base), 2-methyl-4-chloroaniline (Fast Red TR base), 2-meteoxy -5-chloroaniline (Fast Red RC base), 4-nitroaniline (Fast Red 2G base), 2-methoxy-5-: nitroaniline (Fast Scarlet R base), and 3-nitroaniline (Fast Orange R base) as diazo components and 3-hydroxy-2-naphtho-o-anisidide (Naphtol AS-OL) and 3-hydroxy-2-naplitho-o-phenetidide (Naphtol AS-PH) as coupling components, and chloromethylation of the azo compounds has been attempted. Chloromethylat-ion of the azo compounds was possible by treating the azo cornpounds in glacial acetic acid with dry hydrogen chloride and paraformaldehyde or dichloromethyl ether, using anhydrous zinc chloride or phosphoric acid as a catalyst. Phosphoric acid was ineffective as a catalyst for formation of azo compounds from o-anisidine as a diazo comonent and 2-naphthol, 3-hydroxy-2-naphthanilide (Naphtol AS), acetoacetanilide, and 1-phenyl-3-methyl-5-pyrazolone as coupling components as reported in the first series of this report but the phosphoric acid was effective as a catalyst in the preparations of azo compounds in this report. Only one chloromethyl group was introduced in all cases and the position of its entrance was confirmed to be the para position of methoxy group in aryl ring of hydroxynaphtho-o-anisidide and para position of ethoxy group in aryl ring of hydroxymaphtho-o-phenetidide.