Preparation of tin octylbromides by the chemical technique

The direct synthesis of tin octylbromides by the interaction of metallic tin and octylbromide is conducted in the presence of ciystalline iodine and triethylamine  

Raw stock metallic tin (grey powder, 99.5% of the main substance) octylbromide (the boiling point is 201-204 °C) crystalline iodine (the melting point is 112.5-114 °C) triethylamine (the boiling point is 89-90 °C). 

The production of tin octylbromides (Fig. 92) comprises three main stages the synthesis of tin octylbromides and the filtering of the reactive mixture to separate unreacted tin the distillation of excess octylbromide the filtering of the mixture of tin octylbromides and its distillation. 

Cylindrical reactor 4 with a jacket, shielded electric drive agitator and inverse cooler 3 receives a given amount of octylbromide from batch box 1. The hatch receives powderlike tin from transportable bin 2, triethylamine (3-4% of the reactive mixture) and iodine (0.3-0.4%). The hatch is closed and the agitator is switched on. The contents of the apparatus are heated to 170-180 °C and agitated at this temperature for 4-5 hours. Then the reactive mixture is cooled to 20 °C and sent into filter 5 to separate unreacted tin. The filtrate is sent by nitrogen flow into tank 7 to distil excess octylbromide. The solid residue, unreacted tin, is flushed twice with acetone in the filter. After flushing acetone is collected in collector 6, and the flushed tin is used again in the production. 

The distillation of octylbromide in tank 7 is carried out at 60-80 °C and a residual pressure of 5.2-6.6 GPa. Octylbromide is collected in collector 10 and used again in the synthesis of tin octylbromides. After the distillation of octylbromide the mixture of tin octylbromides and solid residue (complex triethylamine salt, which forms sediment during the distillation) is cooled in the tank down to 20-30 °C and sent into filter 8 to separate the solid residue. 

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