Synthesis of indolo[1,2-c]quinazolines from 2-alkynylaniline derivatives through Pd-catalyzed indole formation/cyclization with N,N-dimethylformamide dimethyl acetal

• Antonio Arcadi,
• Sandro Cacchi,
• Giancarlo Fabrizi,
• Francesca Ghirga,
• Antonella Goggiamani,
• Antonia Iazzetti and
• Fabio Marinelli

Beilstein J. Org. Chem. 2018, 14, 2411–2417, doi:10.3762/bjoc.14.218

• or by sequential Pd-catalyzed reaction of o-(o-aminophenylethynyl)aniline with DMFDMA. Keywords: arylboronic acids; DMFDMA; indoles; indoloquinazolines; quinazolines; Introduction Indoloquinazoline derivatives constitute an important class of compounds which exhibit a wide range of biological

• formic acid [15][16], or reactions of 2-(2-bromoaryl)-1H-indoles with aldehydes and aqueous ammonia [17] or with amino acids [18]. An alternative approach to indoloquinazolines is represented by sequential procedures that use 2-alkynylaniline derivatives as starting materials, via their conversion to 2

• hydrolysis of byproducts 11; 3) after extractive work-up, treatment of the crude reaction mixture with an excess of DMFDMA (5 equiv) [28] in DMF at 100 °C to obtain indoloquinazolines 10. The results of this procedure, starting from a variety of o-(o-aminophenylethynyl)trifluoroacetanilides 5 and arylboronic