2,5-Dibromopyrazine synthesis
- Product Name:2,5-Dibromopyrazine
- CAS Number:23229-26-7
- Molecular formula:C4H2Br2N2
- Molecular Weight:237.88
59489-71-3
400 suppliers
$5.00/1g
23229-26-7
246 suppliers
$10.00/1g
Yield:23229-26-7 24.4%
Reaction Conditions:
with hydrogen bromide;bromine;sodium nitrite in water at -15 - 0; for 2 h;
Steps:
32.2 Step 2: Synthesis of 2,5-dibromopyrazine
Step 2:
Synthesis of 2,5-dibromopyrazine
5-bromopyrazin-2-amine (3 g, 17.241 mmol) and bromine (8.2 g, 51.729 mmol) were added to aq. HBr solution at -15° C. Aq. solution of sodium nitrite (2.97 g, 43.0103 mmol) was then added to the mixture over a period of 1 h at -10° C. keeping the internal temperature below 5° C. during addition and stirred for 1 h at 0° C.
Progress of reaction was monitored by TLC.
After reaction completion reaction mass neutralised with 40% NaOH solution and extracted with diethyl ether.
The organic layer was dried over sodium sulphate and concentrated under reduced pressure (below 30° C.) to yield 2,5-dibromopyrazine (1 g, 24.4%) as brown oil.
MS: 238.8[M++1]
References:
Mankind Pharma Ltd.;Patil, Rakesh Ishwar;Verma, Jeevan;Shah, Dharmesh;Ali, Sazid;Bapuram, Srinivasa Reddy;Rai, Santosh Kumar;Kumar, Anil US2017/291910, 2017, A1 Location in patent:Paragraph 0592-0594
290-37-9
339 suppliers
$5.00/5g
23229-26-7
246 suppliers
$10.00/1g
56423-63-3
168 suppliers
$9.00/100mg
23229-26-7
246 suppliers
$10.00/1g