Direct, Two-Step Synthetic Pathway to Novel Dibenzo[a,c]phenanthridines

Abstract

Novel dibenzo[a,c]phenanthridines are prepared regioselectively by the application of a straightforward synthetic pathway, starting from new 3,4-diaryl- and 3,4-dihydro-3,4-diarylisoquinolines prepared via Ritter-type heterocyclization and the more classical two-step reductive amination/Bischler-Napieralski cyclization of triarylethanones, respectively. A comparative study of nonphenolic oxidative coupling methodologies provides a highly efficient procedure, based on the hypervalent iodine reagent phenyliodine(III) bis(trifluoroacetate) (PIFA), to accomplish the final coupling step.

Metal Free, Direct and Selective Deoxygenation of α‐Hydroxy Carbonyl Compounds: Access to α,α‐Diaryl Carbonyl Compounds

“…The deoxygenation of –OH group in α‐hydroxy‐α,α‐diaryl carbonyl compounds can furnish α,α‐diaryl carbonyl compounds, which are an important class themselves . 1,2,2‐Triarylethanones, for example, are very important precursors for the synthesis of dibenzo[ a,c ]phenanthridine, analogues of biologically active benzo[ c ]phenanthridine alkaloids . In addition, 1,2,2‐triarylethanones are also useful synthons for tamoxifen, the most widely used drug for the treatment of breast cancer .…”

Thallium(III) in Organic Synthesis

“…When this oxidative coupling was performed with iodine(III), the product 74 was isolated in lower yield (42% yield). 86…”

Dual behavior of 2‐tetralone: A new approach for the synthesis of 5‐aryl‐7,8,13,14‐tetrahydrodibenzo[a,i]phenanthridine

“…The literature preparations of the phenanthridine ring system have disadvantages, such as, lengthy syntheses, low yields, and structurally complicated precursors [8, 15–20]. Even a synthesis involving a few steps from simple precursors such as formaldehyde and 2‐methylbenzonitrile affords benzo[c]phenanthridine in a 6% overall yield [15].…”