Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...
Patent
1994-01-04
1995-11-21
Springer, David B.
Organic compounds -- part of the class 532-570 series
Organic compounds
Heterocyclic carbon compounds containing a hetero ring...
548250, C07D40312
Patent
active
054688663
ABSTRACT:
Methods of preparing bis-(1(2)H-tetrazol-5-yl)-amine (BTA) having improved physical and chemical characteristics are disclosed. In the process, a dicyanamide salt and an azide salt are reacted at high temperature in the presence of an acid reagent. Best yields are obtained when the reaction is allowed to proceed for approximately 48 hours. The dicyanamide salt is preferably present in a stoichiometric excess. The acid reagent has a pK.sub.a in the range from about 3 to about 9. The reaction mixture is acidified to a pH less than 3. Several variations of the acidification step permit control of particle size and morphology. Small, rounded particles are prepared by rapidly cooling the hot crude reaction product coincidentally with acidification. This is preferably accomplished by adding the hot crude reaction product directly to cold concentrated acid. The precipitated particles are isolated to yield BTA.
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Blau Reed J.
Hajik Robert M.
Highsmith Thomas K.
Lund Gary K.
Wardle Robert B.
Lyons Ronald L.
Springer David B.
Thiokol Corporation
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