Multicomponent pyran synthesis

R = CN, C02Et, CONH2 Scheme 6.245 Multicomponent condensation in the synthesis of tetrahydrobenzo[b]pyrans. 

M11 Yu.M. Litvinov, Multicomponent synthesis of 2-amino-4H-pyrans and... 

L. Chen, Y.-Q. Li, X.-J. Huang, W.-J. Zheng, Heteroatom Chem. 2009, 20, 91-94. AI,AJ-Dimethylamino-functionalized basic ionic hquid catalyzed one-pot multicomponent reaction for the synthesis of 4//-benzo[h]pyran derivatives under solvent-free condition. 

P. R. Nandaluru, G. J. Bodwell, Org. Lett. 2012,14,310-313. Multicomponent synthesis of 6//-dibenzo[fc,rl]pyran-6-ones and a total synthesis of cannabinol. 

Bhattacharyy P, Pradhan K, Paul S, Das AR (2012) Nano crystalline ZnO catalyzed one pot multicomponent reaction for an easy access of fully decorated 4 /7-pyran scaffolds and its rearrangement to 2-pyridone nucleus in aqueous media. Tet Lett 53 4687-4691 Albadi J, Mansournezhad A, Derakhshandeh Z (2013) CuO-CeO nanocomposite a highly efficient recyclable catalyst for the multicomponent synthesis of 4 /7-benzo[6]pyran derivatives. Chinese Chem Lett 24 821-824... 

Chen, T., Xu, X.-P., and Ji, S.-J. (2013). Facile and efficient synthesis of indol-3-yl substituted pyran derivatives via one-pot multicomponent reactions under ultrasonic irradiation. 7. Heterocyclic Chem., 50, 244-251. 

Xie, X., Peng, C., He, G., Leng, H.-J., Wang, B., Huang, W., Han, B. (2012). Asymmetric synthesis of a structurally and stereochemicaUy complex spirooxindole pyran scaffold through an organocatalytic multicomponent cascade reaction. Chemical Communications, 48, 10487-10489. 

A number of mefhods for fhe synthesis of fused pyrans were developed using multicomponent reactions in PEG. Thus, the annulation of a pyran ring using the three-component reaction of 1/5-cyclohexanediones, arylaldehydes, and malononitrile was found to proceed in the presence of barium(II) triflate xmder mild conditions in aqueous PEG 400 providing tetrahydrochromenes 105 (Scheme 58) [89]. The recyclability of the catalyst was studied using the... 

A. Nandakumar, P. Thirumurugan, P.T. PerumaL P. Vembu, M.N. Pormuswamy, P. Ramesh, One-pot multicomponent synthesis and antimicrobial evaluation of 2 -(mdol-3-yl)-2-oxospiro(indoUne-3,4 -pyran) derivatives, Bioorg. Med. Chem. Lett. 20 (2010) 4252-4258. 

D. Tahmassebi, J. A. Bryson, S.l. Binz, l,4 Diazabicyclo[2.2.2]octane as an efficient catalyst for a clean, one-pot synthesis of tetrahydrobenzo[fc] pyran derivatives via multicomponent reaction in aqueous media, Synth. Commun. 41 (2011) 2701-2711. 

G. Brahmachari, S. Laskar, B. Baneqee, Eco-friendly, one-pot multicomponent synthesis of pyran armulated heterocyclic scaffolds at room temperature using ammonium or sodium formate as non-toxic catalyst, J. Heterocylic Chem. 51 (2014) E303-E308. http //dx.doi.org/10.1002/jhe t.l974, article first published online 1 MAY 2014. 

J. Pandey, N. Anand, R.P. Tripathi, L-Proline catalyzed multicomponent reaction of 3,4 dihydro-(2H)-pyran, urea/thiourea, and aldehydes diastereoselective synthesis of hexahydropyranopyrimidinones (thiones). Tetrahedron 65 (2009) 9350-9356. 

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