Cyclization of Chiral Carbon-Centered Aziridinyl Radicals: A New Route to Azirino[2',3':3,4]pyrrolo[1,2-a]indoles

Recent Synthetic Applications of Chiral Aziridines

“…There are few reports of chiral aziridinyl radicals but they have been generated from bromoaziridines. 146,147 Treatment of aziridine epimers 181 with ACCN and Bu 3 SnH under high dilution afforded a chiral aziridinyl radical which cyclised onto the indole functionality (Scheme 45).…”

Oxidative Dearomative Cross-Dehydrogenative Coupling of Indoles with Diverse C-H Nucleophiles: Efficient Approach to 2,2-Disubstituted Indolin-3-ones

“…Under the developed oxidative conditions, indoles have been widely used as nucleophiles in a number of CDC reactions owing to the strong nucleophilicity of indole rings [19][20][21][22][23][24][25][26][27][28][29]. In contrast, reactions of indoles with other nucleophiles have not been well investigated [30][31][32][33][34][35]. Therefore, the development of CDC reactions from indoles with various C-H nucleophiles will provide straightforward access to structurally diverse indole derivatives and is thus highly desired.…”

Transition Metal‐Free, Visible Light‐Mediated Radical Cyclisation of Malonyl Radicals onto 5‐Ring Heteroaromatics

“…Some of the first examples of radical cyclisations onto unsaturated heterocycles involved nucleosides and/or nucleotides. [5][6] From the 1990s, the field expanded rapidly with reports of cyclisations of alkyl, acyl, vinyl, aryl, and malonyl radicals onto a variety of heterocycles including, pyridines/pyridinium ions, [7][8][9][10] indoles, [11][12][13][14][15][16][17][18][19][20][21][22] pyrroles, [13,16,[21][22][23][24][25][26][27][28] imidazoles, [26,[28][29] triazoles, [30] thiophenes, [14,22] and pyrazoles [31] to form fused five, six, and seven-membered rings. Many of these methods used organotin reagents with most studies reporting cyclisations onto a small number of electronically similar heteroaromatics.…”