Heretofore, as a method for producing trimethylsilyl azide, a method in which trimethylsilyl chloride and an inorganic salt of hydrogen azide are reacted in a solvent having a low boiling point such as di-n-butyl ether or diethylene glycol dimethyl ether or bis(2-methoxyethyl)ether has been known (see Non-patent documents 1, 2 and 3).
Further, a method in which trimethylsilyl chloride and an inorganic salt of hydrogen azide carried on a macroporous polymer are reacted in a solvent such as decalin, acetonitrile or dichloromethane has been also known (see Patent document 1 and Non-patent document 4).
Furthermore, a method in which synthesis is carried out using trimethylsilyl chloride and an inorganic salt of hydrogen azide in the absence of a solvent has been reported (see Patent document 2).
However, in the above production methods, there are the following problems (1) to (4).
(1) In the synthesis method using a solvent having a low boiling point, a long time of 48 hours to 60 hours is required until the reaction is completed. Further, in order to shorten the reaction time, it is necessary to use an inorganic salt of hydrogen azide which is carried on a macroporous polymer.
(2) As a method of isolating the resulting trimethylsilyl azide, there is only a method by distillation. In the distillation, trimethylsilyl azide and a solvent are not sufficiently separated, and the solvent is contaminated in trimethylsilyl azide, whereby the purity thereof is decreased. Namely, in order to obtain trimethylsilyl azide with high purity, a multistage precision distillation apparatus is required and therefore equipment therefor is required, which results in increasing the production cost.
(3) In the case where synthesis is carried out in the absence of a solvent, the above problems may be solved. However, there are problems that the load upon starting stirring is extremely large, which imposes the load on the apparatus, that a large amount of heat generation occurs all at once in the initial stage of the reaction, and the like.
(4) The trimethylsilyl azide thus produced can be isolated to high purity only by a simple distillation without resort to a multistage precision distillation apparatus. However, since a solvent is not used, byproduct salts are not dispersed, and therefore, as the distillation procedure is getting closer to the final stage, it becomes more difficult to carry out stirring.
Patent document 1: JP-A-1-143878
Patent document 2: JP-A-10-45769
Non-patent document 1: Synthesis, 2, 106-107 (1988)
Non-patent document 2: Org. Synth., 50, 107 (1970)
Non-patent document 3: J. Amer. Chem. Soc. 84, 1763, (1962)
Non-patent document 4: J. Org. Chem. 53, 20, 4867-4869, (1988)
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