1. Procedure
(A) Nitrosodimethylamine.—In a 2-l. round-bottomed flask provided with a mechanical stirrer are
placed 245 g. (3 moles) of dimethylamine hydrochloride, 120 cc. of water, and 10 cc. of approximately
2 N hydrochloric acid. The resulting solution is stirred vigorously and maintained at 70–75° by heating
on a water bath, while 235 g. (3.23 moles) of 95 per cent sodium nitrite suspended in 150 cc. of water is
added from a dropping funnel over a period of an hour. The reaction mixture is tested frequently and
maintained barely acid to litmus by further 1-cc. additions of 2 N hydrochloric acid when necessary
(about 30–35 cc. of acid is required). Stirring and heating are continued for two hours after all the
sodium nitrite has been added.
The flask is arranged for distillation, and the reaction mixture is distilled under slightly diminished
pressure on a water bath until the residue is practically dry. To the residue 100 cc. of water is added, and
the process of distillation to dryness is repeated. The distillates are combined and saturated with
potassium carbonate (about 300 g. is required); the upper layer of dimethylnitrosoamine is removed, and
the water layer is extracted with three 140-cc. portions of ether. The combined nitrosoamine and
ethereal extracts are dried over anhydrous potassium carbonate and distilled through a 30-cm.
fractionating column. The yield of product boiling at 149–150° /755 mm. is 195–200 g. (88–90 per cent
of the theoretical amount). Nitrosodimethylamine is a yellow oil which darkens in bright light.
(
尤其是第一步的机理？原料，亚硝酸钠，盐酸的量的比例多少最好？为什么？？
maintained barely acid 是什么意思？
各位前辈,下列一段文字小弟看不很懂,可能是文献太老了,一些装置现在不用了吧,哪位前辈能给我翻译一下,或者指点一下啊,了!
The flask is fitted
with a dropping funnel, and the steam inlet is provided with a trap. A large filtering or distilling flask
serves as the receiver, and the side tube is connected with two absorption flasks, each containing 1 : 1
hydrochloric acid (Note 2). The aqueous liquors are made distinctly alkaline by adding a concentrated
solution of 1 kg. of sodium hydroxide through the dropping funnel, and the mixture is then steamdistilled
until a test portion of the distillate shows only a faint reduction with Fehling's solution. Usually
about 5–6 l. of distillate suffices to remove the dimethylhydrazine. The distillation is more rapid if a free
flame is placed under the distillation flask.
这是OS上面的文献，第一步是仲胺的亚硝化。仲胺与亚硝酸反应形成N－亚硝基化合物，在有机书上有介绍。盐酸应该至少等当量，但考虑到使用了盐酸盐，所以文献中补加了催化量的盐酸。反应中亚硝酸钠先与盐酸形成亚硝酸，然后 再氧化胺。
(A) Nitrosodimethylamine.—In a 2-l. round-bottomed flask provided with a mechanical stirrer are
placed 245 g. (3 moles) of dimethylamine hydrochloride, 120 cc. of water, and 10 cc. of approximately
2 N hydrochloric acid. The resulting solution is stirred vigorously and maintained at 70–75° by heating
on a water bath, while 235 g. (3.23 moles) of 95 per cent sodium nitrite suspended in 150 cc. of water is
added from a dropping funnel over a period of an hour. The reaction mixture is tested frequently and
maintained barely acid to litmus by further 1-cc. additions of 2 N hydrochloric acid when necessary
(about 30–35 cc. of acid is required). Stirring and heating are continued for two hours after all the
sodium nitrite has been added.
The flask is arranged for distillation, and the reaction mixture is distilled under slightly diminished
pressure on a water bath until the residue is practically dry. To the residue 100 cc. of water is added, and
the process of distillation to dryness is repeated. The distillates are combined and saturated with
potassium carbonate (about 300 g. is required); the upper layer of dimethylnitrosoamine is removed, and
the water layer is extracted with three 140-cc. portions of ether. The combined nitrosoamine and
ethereal extracts are dried over anhydrous potassium carbonate and distilled through a 30-cm.
fractionating column. The yield of product boiling at 149–150° /755 mm. is 195–200 g. (88–90 per cent
of the theoretical amount). Nitrosodimethylamine is a yellow oil which darkens in bright light.
(
尤其是第一步的机理？原料，亚硝酸钠，盐酸的量的比例多少最好？为什么？？
maintained barely acid 是什么意思？
各位前辈,下列一段文字小弟看不很懂,可能是文献太老了,一些装置现在不用了吧,哪位前辈能给我翻译一下,或者指点一下啊,了!
The flask is fitted
with a dropping funnel, and the steam inlet is provided with a trap. A large filtering or distilling flask
serves as the receiver, and the side tube is connected with two absorption flasks, each containing 1 : 1
hydrochloric acid (Note 2). The aqueous liquors are made distinctly alkaline by adding a concentrated
solution of 1 kg. of sodium hydroxide through the dropping funnel, and the mixture is then steamdistilled
until a test portion of the distillate shows only a faint reduction with Fehling's solution. Usually
about 5–6 l. of distillate suffices to remove the dimethylhydrazine. The distillation is more rapid if a free
flame is placed under the distillation flask.
这是OS上面的文献，第一步是仲胺的亚硝化。仲胺与亚硝酸反应形成N－亚硝基化合物，在有机书上有介绍。盐酸应该至少等当量，但考虑到使用了盐酸盐，所以文献中补加了催化量的盐酸。反应中亚硝酸钠先与盐酸形成亚硝酸，然后 再氧化胺。