Electric Literature of 95-89-6,Some common heterocyclic compound, 95-89-6, name is 3-Chloro-2,5-dimethylpyrazine, molecular formula is C6H7ClN2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
EXAMPLE 23 A solution of phenylmagnesium bromide (1M in THF, 5.6 mL, 5.6 mmol) is added to a solution of 3-chloro-2,5-dimethylpyrazine (346 mg, 2.42 mmol) and Fe(acac)3 (43 mg, 0.12 mmol) in THF (10 mL) at -30 C. After stirring for 30 min at that temperature, the reaction is quenched with brine, the aqueous layer is extracted with Et2O, the combined organic phases are dried over Na2SO4 and evaporated, and the residue is purified by flash chromatography (hexane/ethyl acetate, 10:1). After eluding a first fraction containing biphenyl (212 mg), one obtains 2,5-dimethyl-3-phenylpyrazine as a pale yellow syrup (287 mg, 64%). 1H NMR (300 MHz, CD2Cl2) delta8.31 (s, 1H), 7.55-7.59 (m, 2H), 7.43-7.51 (m, 3H), 2.55 (s, 3H), 2.54 (s, 3H). 13C NMR (75 MHz, CD2Cl2) delta152.7, 150.6, 148.4, 142.1, 139.5, 129.3, 128.7, 128.6, 22.7, 21.2.
The synthetic route of 95-89-6 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Furstner, Alois; Leitner, Andreas; Mendez, Maria; US2003/220498; (2003); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem