Synthesis of substituted imidazolines by an Ugi/Staudinger/aza-Wittig sequence

Combinatorial Chemistry Online Volume 17, Issue 5, May 2015

“…The intramolecular aza-Wittig cyclization between the iminophosphane and the tertiary amide of the Ugi product was achieved by short microwave irradiation. Competitive cyclization to the secondary amide was not relevant, however, in some cases subsequent formation of bicyclic ortho-amidines was observed [3].…”

“…For example the ACD commercially available chemical database shows a slight preponderance of this regioisomer, but it has to be considered whether the bias in drug design follows a real advantage in druglike properties, the intrinsic availability of precursors, or some other deeply held but possibly irrational beliefs by medicinal chemists. Indeed, it is possible to find well regarded marketed drugs with all three isomeric patterns of chlorophenyl: para-chloro in haloperidol (1) and loperamide (2), meta-chloro in bupropion (3) and trazodone (4), ortho-chloro in clopidogrel (5) and ketamine (6). …”

Recent advances in the discovery and design of multicomponent reactions for the generation of small-molecule libraries

“…38 (B) Sequential MCR/elaboration/cyclization strategy. 39 (C) Sequential MCR/cyclization strategy. 40 possibility to further diversify the products via the reaction of the secondary amine group in the thiazolidine ring with a series of isocyanates giving urea derivatives was established (reaction A; Figure 5).…”

“…Sequencing the Ugi-type MCRs with an intramolecular olefin formation via Staudinger/aza-Wittig 39 or Wittig reaction 40 was shown to be a popular synthetic tool. Two selected applications for the preparation of libraries of biologically relevant heterocycles are shown in reactions B and C in Figure 5.…”

Thermally stable imidazoline-based sulfonate copolymers for enhanced oil recovery

“…[16][17][18][19][20] Recently, increasing attention has been paid to multifunctional polymers, especially imidazole-and imidazoline-containing polymers which show a wide range of potential applications. [21][22][23][24][25][26] And the chemical architecture of substituted imidazoline units constituted as the following: a five-membered aromatic heterocyclic containing two nitrogen atoms at the 1, 3-positions (namely, an electron-rich hydrophilic amidine (N=C-N) motif), a hydrophobic alkyl chain and a pendant side chain constituted by electron-donor hydrophilic functional group(s) attached to N of the motif and the C terminal, respectively. 27 Although the particular configuration and characteristic endow imidazoline derivatives with desirable storage stability, viscosity, dispersibility and corrosion inhibition performance in various industrial applications, they were rarely utilized to incorporate into PAM chain for enhanced oil recovery.…”