Three-component synthesis

Fee et al. have investigated the Fewis acid-catalyzed three-component synthesis of a-amino phosphonates [73]. This was carried out in the ionic liquids [BMIM][PFg],... 

Scheme 21 One-pot three-component synthesis of cUhydro-s-triazines...

The one-pot, three-component synthesis of a 20-membered dihydrotri-azine hbrary was also dramatically accelerated through the use of microwave irradiation [79]. Heating a subset of substituted anilines, cyanoguanidine and acetone in the presence of concentrated hydrochloric acid for 35 min at 90 °C in a single-mode microwave reactor gave the corresponding 2,2-dimethyl-1,2-dihydro-s-triazine hydrochloride 51 in comparable yield to conventional conductive heating methods but in a much shorter reaction time and increased purity (Scheme 21). 

Scheme 9.18. Three-component synthesis of furo[2,3-c]quinolines 9-88.

Reaction of pyridines with dialkyl acetylenedicarboxylates in the presence of isocyanates in dry CH2C12 at room temperature produced 1-substituted 2-oxo-l,9a-dihydro-2/7-pyrido[l,2-tf]pyrimidine-3,4-dicarboxylates <2004TL1803>. One-pot, three-component synthesis of 1-substituted 2-oxo-l,llb-dihydro-2//-pyrimido[2,l- ]iso-quinoline-3,4-dicarboxylates and 4-(3-chloro-4-methylphenyl)-3-oxo-4,4a-dihydro-3/7-pyrimido[l,2-tf]quinoline-l,2-dicarboxylate was realized by the reaction of isoquinoline and quinoline with isocyanates and dialkyl acetylenedicarboxylates <2004S861>. Diastereomeric mixtures of l-tosyl-2-aryl-l,llb-dihydro-2/7-pyrimido[2,Ttf]isoquinoline-3,4-dicarboxylates were obtained from isoquinoline, iV-tosyl-benzaldehyde imines, and DMAD <2002OL3575>. 

Scheme 6.246 Biginelli three-component synthesis of dihydropyrimidines.

Scheme 5.32 Regioselective in situ three-component synthesis of 150.

The three-component synthesis of benzo and naphthofuran-2(3H)-ones from the corresponding aromatic alcohol (phenols or naphthols) with aldehydes and CO (5 bar) can be performed under palladium catalysis (Scheme 16) [59,60]. The mechanism involves consecutive Friedel-Crafts-type aromatic alkylation and carbonylation of an intermediate benzylpalla-dium species. The presence of acidic cocatalysts such as TFA and electron-donating substituents in ortho-position (no reaction with benzyl alcohol ) proved beneficial for both reaction steps. 

Shaabani A, Maleki A, Mofakham H, Khavasi HR (2008) Novel isocyanide-based three-component synthesis of 3, 4-thhydroquinoxalin-2-amine derivatives. J Comb Chem 10 (2) 323-326... 

Adib M, Jahromi AH, Tavoosi N et al (2006) Microwave-assisted efficient, one-pot, three-component synthesis of 3, 5-disubstituted 1, 2, 4-oxadiazoles under solvent-free conditions. Tetrahedron Lett 47(17) 2965-2967... 

Zhu s group also developed an ammonium chloride-promoted three-component synthesis of 5-iminooxazole and subsequent transformation to a macrocyclodepsi-peptide [89]. In this approach, a three-component reaction of an a,a-disubstituted a-isocyanoacetamide 21a, an aldehyde, and an amino alcohol b afforded the 5-iminooxazole c, which was cyclized after saponification under acidic conditions to furnish the macrocyclodepsipetides d (Scheme 21). 

Scheme 6 Three-component synthesis of pyridines upon exposure to air...

Scheme 11 Ecocompatible three-component synthesis of dihydropyridopyrimidinone derivatives...

Scheme 14 Three-component synthesis of hexahydropyrimidine derivatives...

Scheme 15 Three-component synthesis of spiroheterocyclic Biginelli s products...

Scheme 23 [Yh(PFO)3]-catalyzed three-component synthesis of fully substituted pyrazoles...

Scheme 31 Catalyst-free three-component synthesis of functionalized imidazolones...

Scheme 37 Three-component synthesis and reactivity of hemi-ketal tetrahydrochromene derivatives...

Scheme 44 Three-component synthesis of chromenone derivatives from Meldrum s acid...

Scheme 47 InCls-catalyzed three-component synthesis of 2-pyrrolo-3 -yloxindoles...

Scheme 48 Lewis acid-catalyzed three-component synthesis of 3,3 -bipyrroles...

Scheme 50 Three-component synthesis of chiral, bicyclic functionalized tetrahydropyridines...

Scheme 56 Regioselective 4 A MS-promoted three-component synthesis of pyridines...

Scheme 60 Three-component synthesis of polycyclic pyrrolopiperazine scaffolds...

Scheme 61 Three-component synthesis of 2,6-DABCO skeletons...

Scheme 63 Three-component synthesis of 2,3-dihydropyran[2,3-c]pyrazoles...

Shen L, Cao S, Liu NJ, Wu JJ, Zhu LJ, Qian XH (2008) Ytterbium(III) perfluorooctanoate catalyzed one-pot, three-component synthesis of fully substituted pyrazoles under solvent-free conditions. Synlett 1341-1344... 

Nagarapu L, Bantu R, Mereyala HB (2009) TMSCl-mediated one-pot, three-component synthesis of 2H-indazolo 2, 1-b phthalazine-triones. J Heterocycl (Them 46 728-731... 

Zhu SL, Ji SJ, Zhang Y (2007) A simple and clean procedure for three-component synthesis of spirooxindoles in aqueous medium. Tetrahedron 63 9365-9372... 

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