Synthesis of new di-(3-indolyl)arenes

Synthesis of Imine and Amine-Linked Macrocycles Containing Tris-Indoles

“…Since the synthesis of 7-nitroethylindoles 11a,b was reported, [20] they were reacted with excess formaldehyde in glacial acetic acid, following previous routes to 2,2 0 -diindolylmethanes. [11,12,[14][15][16]21] Although the reaction proceeded, a complex mixture of products was obtained. However, the preparation of methylene bridged 2,2 0 -bis-indoles 12a,b was achieved successfully by the condensation of 7-nitroethylindoles 11a,b with an excess of formaldehyde in the presence of hydrochloric acid in anhydrous methanol (Scheme 2).…”

“…For example, the dialdehyde 6 reacts with 2,2 0 -diaminodiphenylamine (4) to give the 18-membered macrocyclic diindolylmethane diimine 7 (Scheme 1). [11] More recently, dialdehydes derived from di-(2-indolyl)arenes [12] and di-(2-indolyl)heteroarenes [13] have been shown to undergo reactions with diamines to give macrocyclic compounds containing three and four indoles. Furthermore, the synthesis of new macrocyclic systems incorporating 2,2 0 -diindolylmethane moieties has a special interest.…”

Some electrophilic reactivity studies of di-(2-indolyl)dibenzofurans and di-(2-indolyl)carbazoles

“…Compounds 1, 3 and 4 have already been reported by us, 2 and details for preparation of compounds 2, 5 and 6 are recorded in the Experimental section. Formylation occurred smoothly at the indole C3 positions and compounds 7e12 were formed in high yield (Scheme 1).…”

“…Water (20 mL) was added to the dark brown solution and the mixture was extracted with diethyl ether (3Â100 mL). After washing each ether extract with water (3Â30 mL), the ethereal phases were combined, dried over sodium sulfate and concentrated, giving the trimethyl di-indolyl carbazole 5 as yellow crystals (0.79 g, 72%), mp 128e130 C; IR (KBr): n max 3422, 3049,1603,1486,1467,1422,1359,1336,1313,1283,1251,1126,952,750 1,109.9,120.1,120.6,121.7,121.7,128.1 (aryl CH),123.1,124.2,128.5,138.6,141.4,142.8 (aryl C); HRMS (ESI):…”

“…1,2 We have previously reported the synthesis of some di-(3-indolyl)heteroarenes 1 and some di-(2-indolyl)heteroarenes 2 in which the linker between the two indoles is a dibenzofuran or a carbazole. The indoles were substituted at the readily functionalizable C2 and C8 positions on the central heterocyclic system.…”