ChemicalBook CAS DataBase List 2 4'-METHYLENEBIS(PHENYL ISOCYANATE)

2 4'-METHYLENEBIS(PHENYL ISOCYANATE) synthesis

2synthesis methods

Product Name:2 4'-METHYLENEBIS(PHENYL ISOCYANATE)
CAS Number:5873-54-1
Molecular formula:C15H10N2O2
Molecular Weight:250.25

75-44-5
2 suppliers
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1208-52-2
83 suppliers
$75.00/25 mg

6582-52-1 Synthesis

6582-52-1
34 suppliers
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101-77-9 Synthesis

101-77-9
340 suppliers
$15.00/25g

2536-05-2
12 suppliers
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5873-54-1
23 suppliers
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101-68-8 Synthesis

101-68-8
244 suppliers
$13.00/25g

Yield:-

Reaction Conditions:

in chlorobenzene at 0;Product distribution / selectivity;Heating / reflux;

Steps:

1.b; 2.b
b) Production of a Mixture of Di- and Polyisocyanates; The 1,900 g of the mixture of di- and polyamines obtained in Example 1 a) were dissolved in 5,700 g of chlorobenzene in another stirred reactor. In a second vessel, a 33 wt. % (based on the weight of the solution) phosgene solution was prepared by dissolving 3,800 g of phosgene in 7,600 g of chlorobenzene, while cooling to 0° C., and the amine and phosgene solutions were mixed while stirring intensively. The resulting suspension of solids was heated slowly with the formation of hydrogen chloride gas, which was withdrawn in a suitable manner. A homogeneous solution of polyisocyanate was formed during this process. The solvent was separated off by distillation, which resulted in 2,370 g of a mixture of di- and polyisocyanates of the following composition being obtained: 4,4'-MDI: 59.3 wt. %, 2,4'-MDI: 5.5 wt. %, 2,2'-MDI: 0.2 wt. %, higher molecular weight polyisocyanates: 35 wt. %, based on the weight of the mixture.; b) Production of the Polyisocyanate Mixture; The mixture of di- and polyamines obtained in Example 2 a) was reacted with phosgene in chlorobenzene in the same way as described in Example 1, with the same molar ratio of phosgene to amino groups as in Example 1, to form the polyisocyanate mixture. 2,330 g of a polyisocyanate mixture of the following composition were obtained: 4,4'-MDI: 44.1 wt. %, 2,4'-MDI: 7.2 wt. %, 2,2'-MDI: 0.5 wt. %, higher molecular weight polyisocyanates: 48.2 wt. %, based on the weight of the mixture.

References:

Bayer MaterialScience AG US2007/117997, 2007, A1 Location in patent:Page/Page column 3-4

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