以芳甲酰环氧乙烷和烯胺酮为起始原料,对甲基苯磺酸(PTSA)为促进剂,N,N-二甲基甲酰胺(DMF)溶剂中100 ℃经原位开环-氢迁移/分子内环化,合成了一系列呋喃并[3,4-b]吡啶衍生物,优化收率在70%~78%之间.红外光谱、核磁共振氢谱和高分辨率质谱证实了产物的结构,且通过X-单晶衍射确认了化合物3a的结构.
By using 2,3-epoxypropan-1-ones and enaminoketone, a PTSA-promoted in situ ring opening-hydrogen migration/intramolecular cyclization reaction at 100 ℃ was developed in DMF, affording a series of furano [3,4-b] pyridine derivatives in 70%~78% yields. The structures of all products were characterised by IR spectra, 1H NMR and HRMS. In addition, single-crystal X-ray diffraction confirmed the structure of compound 3a.
[1] Kuethe I T.A concise synthesis of functionalized 2,3-dihydrofuro [3,2-b],[3,2-c] and [2,3-b] pyridines[J].Tetrahedron,2019,75(34):130446.
[2] Jasselin-Hinschberger A,Comoy C,Chartoire A,et al.Successive regioselective metalations of fused heterocycles:synthesis of polyfunctionalized furo[3,2-b] pyridines[J].The Journal of Organic Chemistry,2013,78(11):5618-5626.
[3] Chavan S P,Khairnar L B,Pawar K P,et al.Enantioselective syntheses of(R)-pipecolic acid,(2R,3R)-3-hydroxypipecolic acid,β-(+)-conhydrine and(－)-swainsonine using an aziridine derived common chiral synthon[J].RSC Advances,2015,5(62):50580-50590.
[4] Hogenkamp D J,Ford-Hutchinson T A,Li W Y,et al.Design,synthesis,and activity of a series of arylpyrid-3-ylmethanones as type I positive allosteric modulators of α7 nicotinic acetylcholine receptors[J].Journal of Medicinal Chemistry,2013,56(21):8352-8365.
[5] Sharma U,Ahmed S,Boruah R C.A facile synthesis of annelated pyridines from β-formyl enamides under microwave irradiation[J].Tetrahedron Letters,2000,41(18):3493-3495.
[6] Wang X,Zou W,Xiao H,et al.Electrophysiological characterization of furo [3,2-b] pyridine derivatives as negative allosteric modulator of a7 nicotinic acetylcholine receptor[J].Journal of Chinese Pharmaceutical Sciences,2019,28(3):167-173.
[7] Lin Y,Yang X,Pan W,et al.One-step synthesis of diverse pyridine-containing heterocycles with 3-ethoxycyclobutanones at room temperature[J].Organic Letters,2016,18(9):2304-2307.
[8] Liu J Y,Li Q Y,Jiang B,et al.Three-component domino reactions providing rapid and efficient routes to fully substituted pyrroles[J].RSC Advances,2013,3(15):5056-5068.
[9] 杨峥,解恒参,丁维华,等.1,3,5-三芳基吡唑衍生物的高效合成方法[J].兰州理工大学学报,2021,47(5):65-69.
[10] 黄科文,陈嘉雄,戴雷,等.基于咪唑并吡啶的双极性绿色磷光主体材料合成及其性能[J].发光学报,2022,43:518-527.
[11] Vuillermet F,Bourret J,Pelletier G.Synthesis of imidazo [1,2-a] pyridines:triflic anhydride-mediated annulation of 2H-azirines with 2-chloropyridines[J].The Journal of Organic Chemistry,2021,86(1):388-402.
[12] Wang Y,Zhou Y,Song Q L. [3+1+1] type cyclization of ClCF2COONa for the assembly of imidazoles and tetrazoles via in situ generated isocyanides[J].Chemical Communications,2020,56(45):6106-6109.
[13] Liu K,Chang X,Wang C.Nickel(Ⅱ)-catalyzed cascade vinylogous mukaiyama 1,6-Michael/Michael addition of 2-silyloxyfuran with N-sulfonyl-Ⅰ-azar-Ⅰ,3-dienes:access to fused piperidine/butyrolactone skeletons[J].Organic Letters,2016,18(24):6288-6291.
[14] Cao J,Fang R,Liu J Y,et al.Organocatalytic regiodivergent C-C bond cleavage of cyclopropenones;a highly efficient cascade approach to enantiopure heterocyclic frameworks[J].Chemistry:A European Journal,2018,24(71):18863-18867.
[15] Liu Y W,Ma R J,Yan J H,et al.Asymmetric synthesis of(—)-sedacryptine through a diastereoselective Mannich reaction of N,O-acetals with ketones[J].Organic & Biomolecular Chemistry,2018,16(5):771-779.
