Organic Chemistry of Explosives

322 N-Heterocycles

with 2,4-pentanedione, followed by oxidation of the resulting dihydrotetrazine (196) to the

tetrazine (197) and treatment of the latter with ammonia under pressure.^124 3,6-Diamino-

1,2,4,5-tetrazine (198) is also synthesized from the condensation of 1,3-diaminoguanidine

hydrochloride (199) with 2,4-pentanedione, followed by oxidation of the resulting dihydrote-

trazine (200) with sodium perborate.^125

NN

NN

NH 2

NH 2

198

NN

NN

NHCH 2 C(NO 2 ) 2 X

NHCH 2 C(NO 2 ) 2 X

203, X = NO 2

204, X = F

NN

NN

NH 2

NO 2

202

OO

NN

NN

NH 2

NH 2

201

(LAX-112)

O

O

HOCH 2 C(NO 2 ) 2 X

H 2 O 2

NaOAc (aq)

oxone (aq)

TFA, 90 % H 2 O 2

Figure 7.74

Oxidation of 3,6-diamino-1,2,4,5-tetrazine (198) with oxone in the presence of hydro-

gen peroxide yields 3,6-diamino-1,2,4,5-tetrazine-2,4-dioxide (201) (LAX-112).^126 The same

reaction with 90 % hydrogen peroxide in trifluoroacetic acid yields 3-amino-6-nitro-1,2,4,5-

tetrazine-2,4-dioxide (202).^126 Treatment of 3,6-diamino-1,2,4,5-tetrazine (198) with 2,2,2-

trinitroethanol and 2,2-dinitro-2-fluoroethanol generates the Mannich condensation products

(203) and (204) respectively.^127 ,^128

NN

NN

N

NN

N

H 3 C

H 3 C CH 3

CH 3

NN

NN

NN

NN

NN

N

N

H 3 C

N CH 3

N

CH 3 BrBr

NN

NN

NN

NN

NN

H 2 N NH 2

NN

NN

NN

NN

NN

N

N

H 3 C

N CH 3

N

H 3 C

CH 3

197

205

207 206

(DAAT)

NBS, 98 %

DMSO, NH 3

44 %

0.5 eq N 2 H 4 ,

i-PrOH

79 %

H 3 C

Figure 7.75

Chemists^129 at Los Alamos National Laboratory treated the bis(pyrazoyl)tetrazine (197)

with 0.5 equivalents of hydrazine hydrate and obtained the azotetrazine (205); oxidation of

the latter withN-bromosuccinimide, followed by treatment with ammonia in DMSO, yields