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Organic ChemistryIChO

Organic Chemistry Chemistry Question

Inorganic chains and rings

5.1.

The interaction of thionyl chloride and sodium azide at –30°С gives colorless crystals Х, containing 36.4 wt.% of Cl. The crystals consist of cyclic trimers. Find the composition of X and give the reaction equation.

Model Answer

3 SOCl2 + 3 NaN3 → [NS(O)Cl]3 + 3 NaCl + N2
X – [NS(O)Cl]3

5.2.

Draw two stereoisomers of Х.

5.3.

A colorless liquid Y was prepared by a reaction between X and antimony(III) fluoride. Addition of 1.00 g of Y to the excess of barium acetate aqueous solution gave the precipitate with the mass of 3.96 g. Determine the chemical formula of Y, draw its structure and write the reaction equation.

Model Answer

Y – [NS(O)F]3
2 [NS(O)F]3 + 9 Ba(CH3COO)2 + 18 H2O → BaF2↓ + 6 BaSO4↓ + 12 CH3COOH + 6 CH3COONH4

5.4.

Y enters the substitution reactions with typical nucleophiles such as methylamine. What product will be formed in the reaction between Y and the excess of methylamine? Draw its structure.

Model Answer

[NS(O)(NHCH3)]3

5.5.

Give two examples of molecules or ions which are isoelectronic to Y, draw their structures.

Model Answer

and (SO3)3

5.6.

One of the substances isoelectronic to Y transforms in the presence of water traces into polymer Z. 1.00 g of Z was dissolved in water and the resulting solution was added to the excess of barium acetate solution. The precipitate with the mass of 2.91 g was formed. Determine the formula of Z and draw its structure.

Model Answer

Z = (SO3)n

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