Carbamic acid, ethyl ester → Toluene 2,4-Diisocyanate

HRID 1657902

反応式

HRID 1657902 の反応式
[N-]=C=O.NC(OCC)=O.[C:10]1([CH3:28])[C:11]([NH:22][C:23](OCC)=[O:24])=[CH:12][C:13]([NH:16][C:17](OCC)=[O:18])=[CH:14][CH:15]=1>>[CH3:28][C:10]1[CH:15]=[CH:14][C:13]([N:16]=[C:17]=[O:18])=[CH:12][C:11]=1[N:22]=[C:23]=[O:24]

参加物

4

反応物 3

HCID 5641Carbamic acid, ethyl esterHCID 105034IsocyanateHCID 343975Diethyl toluene-2,4-dicarbamate

生成物 1

HCID 11443Toluene 2,4-Diisocyanate

実験手順

A more recent British Pat. No. 1,247,451 (1971) discloses that it was known that organic isocyanates can be produced by the non-catalytic pyrolysis of urethanes at temperatures above 250° C. but the yield is undesirably low, and if lower temperatures are employed the isocyanate and alcohol will react to reform the original urethane. This confirms the findings discussed hereinbefore wherein various expedients such as catalysts and low pressures were employed with specific carbamates. The aforementioned British patent proposes to pyrolyze diethyl toluene-2,4-dicarbamate in the presence of a Lewis acid such as ferric chloride catalyst to produce toluene-2,4-diisocyanate (TDI). A yield of approximately 59 mole percent is shown. In general, the reaction is carried out at from 400° C. to 600° C. in the presence of the catalyst at subatmospheric pressures to form vapors, and condensing the vapors to recover the organic isocyanate product.

後処理

  1. customwill react

出典と根拠

ORDレコード
ord-d3a13ed5c3114cc99006b2d7a3d0db65
出典データセット
uspto-grants-1976_06
特許番号
US03962302

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