Some common heterocyclic compound, 2423-65-6, name is Pyrazine 1-oxide, molecular formula is C4H4N2O, 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. Product Details of 2423-65-6
General Procedure 2:; Palladium-Catalyzed Direct Arylation with Aryl Chlorides and Bromides.; To a dried flask was added the diazine N-oxide (1.0 to 3.0 equiv.), K2CO3 (2.0 equiv.), Pd(OAc)2 (5 mol %) and HP(t-Bu)3BF4 (15 mol %). If the arylhalide is a solid, it is added at this point (1.0 equiv.). The flask and its contents were then purged under nitrogen for 10 minutes. If the aryl halide is a liquid, it is added via syringe after purging, followed by the addition of degassed dioxane (to produce a reaction concentration of 0.3 M relative to the halide). The reaction mixture was then heated at 110 C. until the reaction was complete, after which the volatiles were removed under reduced pressure and the residue was purified via silica gel column chromatography.2-Mesitylpyrazine N-oxide (Table 4, Entry 5) Synthesised according to general procedure 2. Purification via silica gel column chromatography using 100% DCM then a mixture of 15% Acetone/DCM gave a beige solid 70% yield with 2 eq. of the N-oxide and 76% yield with 3 eq. of the N-oxide. 1H NMR (300 MHz, CDCl3, 293K, TMS): delta 8.45 (1H, d, J=3.9 Hz) 8.42 (1H, s), 8.26 (1H, d, J=4.2 Hz), 7.00 (2H, s), 2.34 (3H, s), 2.07 (6H, s). 13C NMR (75 MHz, CDCl3, 293K, TMS): 149.4, 146.2, 145.3, 140.0, 137.2, 134.3, 128.5, 125.7, 21.1, 19.4.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2423-65-6, its application will become more common.
Reference:
Patent; University of Ottawa; US2008/132698; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem