A convenient three-component reaction for the construction of multifunctional 6-fluoroalkyl-1,2,3,4-tetrahydropyrimidines

Synthesis and substitution reactions of β-alkoxyvinyl bromodifluoromethyl ketones

“…Liu also reported the threecomponent reaction of fluorine-containing enaminoketones or 3-fluoroalkylanilinoacrylic acid esters with primary amines and formaldehyde [17]. b-Aminovinyl bromodifluoromethyl ketones 2 were prepared from enone 1a in good to excellent yields (Scheme 2 and Table 2) for their further transformation.…”

“…For instance, the characteristic features of the 1 H NMR in CDCl 3 spectra of 2b were the appearances of doublets centered at 5.32 ppm and 7.23 ppm with 3 J H-H = 7.1 Hz for 3-H and 4-H protons, respectively, indicating the cis configuration of the vicinal two hydrogen atoms. The trans configuration of the N,Ndimethylenaminone 2d was also based on the appearances of doublets centered at 5.25 ppm and 7.85 ppm with 3 J H-H = 12.2 Hz in the 1 H NMR spectra The three-component reaction of N-monosubstituted enaminoketones 2a and 2b with primary amines and formaldehyde were proceeded in DMF at 110 8C with a mole ratio of 1:3:6.5 (2:primary amines:HCHO) (Scheme 3) according to the reference optimum condition [17]. As shown in Table 3, aliphatic primary amines reacted readily with 2a, 2b and formaldehyde to give multifunctional 1,2,3,4-tetrahydropyrimidine 3 in moderate yields.…”

Octahydropyrimido[4,5-g]quinazoline-5,10-diones: their multicomponent synthesis, self-assembly on graphite and electrochemistry

“…Inspired by the synthesis of 1,2,3,4-tetrahydrobenzo[g]quinazolin-5,10-diones from naphthoquinone derivatives, [11][12][13] and by the many Mannich-aminal condensations of enaminones towards tetrahydropyrimidines, [14][15][16][17][18][19] the reaction of p-dialkylaminoquinones towards octahydropyrimido[4,5-g]quinazolin-5,10diones was optimized. To the best of our knowledge, octahydropyrimido[4,5-g]quinazolin-5,10-diones have not been previously described.…”