[2] GUO W, ZHAO M M, FAN X L, et al. Developments towards synthesis of N-heterocycles from amidines via C-N/C-C bond formation[J]. Organic Chemistry Frontiers, 2019, 6(13): 2120-2141.
[3] WANG M, LIU X W, GAO C. Bicyclization of 4-cyano-1,2-diketones with amidines: synthesis of tetrahydroimidazo[4,5-b]-5-pyridinones[J].The Journal of Organic Chemistry,2022,87(16):11274-11280.
[4] GUO W, FAN X L, ZHAO M M, et al. Base-promoted metal-/oxidant-free three-component tandem annulation: a strategy for the construction of 2,4,5-trisubstituted thiazoles via C-N bond cleavage of amidines[J].Asian Journal of Organic Chemistry, 2018, 7(9):1893-1897.
[5] ZHENG L Y, GUO W, FAN X L, et al. Metal-free, TBHP-mediated, [3+2+1]-type intermolecular cycloaddition reaction: synthesis of pyrimidines from amidines, ketones, and DMF through C(sp3)-H activation[J]. Asian Journal of Organic Chemistry, 2017, 6(7): 837-840.
[6] POLY S S, HASHIGUCHI Y, FUJITANI T, et al.Direct synthesis of triazines from alcohols and amidines using supported Pt nanoparticle catalysts via the acceptorlessdehydrogenativemethodology[J]. Catalysis Science & Technology,2022,12(15): 4679-4687.
[7] VADAGAONKAR K S, KALMODE H P,CHASKAR A C, et al. Greener [3+3] tandem annulation-oxidation approach towards the synthesis of substituted pyrimidines[J]. New Journal of Chemistry, 2015, 39(5): 3639-3645.
[8] DE R, SENGUPTA U, BERA M K, et al.A practical and cost-effective approach to polysubstituted pyrimidine derivatives via DBU mediated redox isomerization of propargyl alcohol and subsequent N-C-N fragment condensation[J]. New Journal of Chemistry, 2022, 46(22): 10603-10610.
[9] QIN Z M, MA Y M, LI F Z. Construction of a Pyrimidine Framework through [3 + 2 + 1] annulation of amidines, ketones, and N,N-Dimethyl-aminoethanol as One Carbon Donor[J]. The Journal of Organic Chemistry, 2021, 86(19): 13734-13743.
[10] JIA F C, ZHOU Z W, WUA X, et al.Divergent synthesis of quinazolin-4(3H)-ones and tryptanthrins enabled by a tert-butyl hydroperoxide/K3PO4-promoted oxidative cyclization of isatins at room temperature[J].Organic Letters, 2016, 18(12): 2942-2945.
[11] DUBEY AV ,KUMAR A V. Cu(II)-glucose:sustainable catalyst for the synthesis of quinazolinones in a biomass-derived solvent 2-methylTHF and application for the synthesis of diproqualone[J]. ACS Sustainable Chemistry & Engineering, 2018, 6(11): 14283-14291.
[12] XU C, JIAF C, WU A X,et al. Dimethyl sulfoxide serves as a dual synthon: construction of 5-methyl pyrimidine derivatives via four component oxidative annulation[J].Advanced Synthesis & Catalysis,2018, 360(12): 2267-2271.
[13] ZHU C L, LIU C, JIANG H F, et al.Transition-metal free selective C(α)-C(β) bond cleavage of trifluoromethyl ketones with amidines under air: facile access to 5-trifluoromethylated Imidazol-4-ones[J]. Organic Chemistry Frontiers,2019, 6(6): 858-862.
[14] LI W H, GAO W C, LI X, et al.Access to highly functionalized imidazolones bearing α-amino acid esters via KOH-promoted annulation of amidines, nitrosoarenes and malonicesters[J]. Organic & Biomolecular Chemistry,2021,19(29):6473-6477.
[15] XIE F, LI Y B, ZHANG M, et al.OMS-2 nanorod-supported cobalt catalyst for aerobic dehydrocyclization of vicinal diols and amidines: Access to functionalized imidazolones[J]. Journal of Catalysis,2021, 398: 192-197.
[16] WANG S, LUO N L, WANGCD, et al. DBU-mediated cyclization of acylcyclopropanecarboxylates with amidines: access to polysubstituted pyrimidines[J]. Organic Letters,2019, 21(12): 4544-4548.
[17] YU X X, ZHOU Y, SONG Q L, et al.Transition metal-free assembly of 1,3,5-triazines using ethyl bromodifluoroacetate as C1 source[J].Chemical Communications,2019, 55(56): 8079-8082.
[18] WANG A A, LIU X S, JIANGTS, et al. Substrate-induced DMSO activation and subsequent reaction for rapid construction of substituted pyrimidines[J].Organic Chemistry Frontiers, 2021, 8(5): 947-952.
[19] GAO Q H, WU M M, XUY T, et al. I2-catalyzed aerobic α,β-dehydrogenation and deamination of tertiary alkylamines: highly selective synthesis of polysubstituted pyrimidines via hidden acyclic enamines[J].Organic Letters, 2020, 22(14): 5645-5649.
[20] SUN L W, SHEN Z L, CHU X Q, et al. Transition-metal-free hydroamination/defluorination/cyclization of perfluoroalkyl alkynes with amidines[J].Organic Chemistry Frontiers,2022, 9(1): 109-116.
[21] CHEN Y L, SHEN Z L, CHU X Q, et al. Four-component defluorinative reaction of allylic fluorides, amidines, and Cs2CO3 under transition-metal-free conditions[J]. Green Chemistry,2022,24(18):6816-6822.
[22] GUO W, HUANGK B, JIANG H F, et al. A facile approach to synthesize 3,5-disubstituted-1,2,4-oxadiazoles via copper-catalyzed-cascade annulation of amidines and methylarenes[J].Chemical Communications,2015, 51(42): 8857-8860.
[23] XIE H, HUANG H W, DENG G J, et al. A three-component approach to 3,5-diaryl-1,2,4-thiadiazoles under transition-metal-free conditions[J].Organic Letters,2016, 18(9): 2196-2199.
[24] YU W T, WU W Q, JIANG H F, et al. Copper-catalyzed aerobic oxidative [3+2] annulation for the synthesis of 5-amino/imino-substituted 1,2,4-thiadiazoles through C-N/N-S bond formation[J].The Journal of Organic Chemistry,2018, 83(16): 9334-9343.
[25] ZHANG J, ZHENG T T, ZHANG J D. I2/K2S2O8 mediated direct oxidative annulation of alkylazaarenes with amidines for the synthesis of substituted 1,3,5-triazines[J].European Journal of Organic Chemistry,2020, 2020(7): 860-865.
[26] ZHANG Y R, GU R, HAN S Q, et al. An alternatively metal-free synthesis of 1,3,5-triazines or 1,2,4-thiadiazoles from benzyl chlorides and benzylamines mediated by elemental sulfur[J]. Tetrahedron Letters,2019, 60(49): 151289.
[27] GUO W, WU W Q, JIANG H F, et al. Transition metal free intermolecular direct oxidative C-N bond formation to polysubstitutedpyrimidines using molecular oxygen as the sole oxidant[J].The Journal of Organic Chemistry,2016, 81(13): 5538-5546.
[28] LIU D Q, GUO W, JIANG H F, et al.Base-mediated three-component tandem reactions for the synthesis of multisubstituted pyrimidines[J].The Journal of Organic Chemistry,2017, 82(24): 13609-13616.
[29] ZHAN J L, CHEN F, HAN B, et al. Cu-Catalyzed [3 + 3] annulation for the synthesis of pyrimidines via β-C(sp3)-H functionalization of saturated ketones[J].The Journal of Organic Chemistry,2016, 81(23): 11994-12000.
[30] ZHANG M M, ZHAN Z Z, HUANG G S, et al. Direct synthesis of 2,4,6-trisubstituted pyrimidines via base-mediated one-pot multicomponent reaction[J]. ChemistrySelect,2021, 6(47): 13627-13632.
[31] CAO W B, XU X P, JIS J, et al. Copper-catalyzed construction of eight-membered rings via oxidative ring expansion and intermolecular cyclization sequencing of indoles with amidines: efficient synthesis of benzo[1,3,5]triazocin-6(5H)-ones[J]. Chemical Communications,2017,53(49):6601-6604.
[32] ZHANG L L, XU X P, JI S J, et al. Visible-light-induced oxidative ring expansion of indoles with amidines[J].Organic Chemistry Frontiers,2019, 6(11): 1787-1795.
[33] GUO W, WU W Q, JIANG H F, et al. Cu-catalyzed intermolecular [3+3] annulation involving oxidative activation of an unreactive C(sp3)-H bond: access to pyrimidine derivatives from amidines and ketones[J]. Organic Chemistry Frontiers,2017,4(6):1107-1111.
[34] TANG L, WANG Z H, ZHANG W, et al. Flower-like Au@CeO2 core-shell nanospheres as efficient photocatalyst for multicomponent reaction of alcohols and amidines[J/OL].Asian Journal of Organic Chemistry,2022, 11(7) [2022-08-31].https://onlinelibrary.wiley.com/doi/10.1002/ajoc. 202200147. DOI: 10.1002/ajoc.202200147.
[35] CHAKRABORTY G, MANDAL S, PAUL N D, et al.Nickel-catalyzed synthesis of pyrimidines via dehydrogenative functionalization of alcohols[J]. Asian Journal of Organic Chemistry,2020,9(3): 431-436.
[36] LIANG F S, BI X H,NISHIDE H,et al. Ambient- light-promoted three-component annulation: synthesis of perfluoroalkylated pyrimidines[J]. Organic Letters,2017, 19(9): 2358-2361.
[37] SCHMITT E, COMMARE B, PANOSSIAN A, et al.Synthesis of mono- and bis(fluoroalkyl)pyrimidines from FARs, fluorinated acetoacetates, and malononitrile provides easy access to novel high-value pyrimidine scaffolds[J]. Chemistry-A European Journal,2017, 24(6): 1311-1316.
[38] CHU X Q, SHEN Z L, LOH T P, et al. Copper- catalyzed three-component cyclization of amidines, styrenes, and fluoroalkyl halides for the synthesis of modular fluoroalkylatedpyrimidines[J].Chemical Communications,2018, 54(21): 2615-2618.