Synthesis of Pyrrolo-/Indolo[1,2-a]quinolines and Naphtho[2,1-b]thiophenes from gem-Dibromovinyls and Sulphonamides

Abstract

A highly efficient and simple route for the synthesis of pyrrolo-/indolo[1,2-a]quinolines and naphtho[2,1-b]thiophenes from gem-dibromovinyls and sulphonamides is reported. The noteworthy feature of this report is that the methodology involves a two-step protocol to synthesize tri- and tetracyclic heterocycles in a one-pot fashion through the Cu(I)-catalyzed formation of ynamide followed by a Ag(I)-assisted intramolecular hydroarylation. The photophysical properties of representative examples of pyrrolo- and indolo[1,2-a]quinolines in solid and solution states have also been studied.

Metal‐Free Cyclization ofortho‐Nitroaryl Ynamides and Ynamines towards Spiropseudoindoxyls

“…When bromoalkyne 5 was used in a similar fashion as in the procedure developed by Hsung and co‐workers, polycycle 4 a was formed rather than the proposed ynamide 3 a . In contrast, the use of dibromoalkene 1 a resulted in the clean formation of ynamide 3 a –. Heating a solution of the purified ynamide in dry THF also resulted in the formation of polycycle 4 a .…”

Indium(III)‐Catalyzed Cyclization of Aromatic 5‐Enynamides: Facile Synthesis of 2‐Aminonaphthalenes, 2‐Amino‐1H‐indenes, and 2,3‐Dihydro‐1H‐indeno[2,1‐b]pyridines

“…Next, the use of 5 mol% of the Au(I) cation, formed in situ from AuCl(PPh 3 ) and AgOTf, in DCM at room temperature for 5 d led to a 49% yield of 2a (Table 1, entry 3). It has been known that AgOTf is capable of catalyzing intramolecular hydroarylation of aromatic ynamide‐tethered pyrroles to afford pyrrolo[1,2‐ a ]quinolines in good yields 11a. However, when subjected to 5 mol% of AgOTf in DCM for 2 d, 1a delivered 2a in only 47% yield (Table 1, entry 4).…”

“…Many transition metal catalysts, including Rh,3 Pd,4 Pt,5 Cu,6 Ag,7 Co,8 and gold,9 have been employed for intramolecular cyclization of ynamides with an alkene or alkyne. In contrast to various transition metal‐catalyzed cyclization reactions, acid‐promoted intramolecular cyclizations of ynamides with tethered unsaturated CC bonds were limited to the HNTf 2 ‐catalyzed cyclization of aromatic ynamides,10a the TsOH‐catalyzed cyclization of ynamides with an alkyne,10b the AgOTf‐catalyzed cycloisomerization reactions of heteroaromatic ynamides11a and epoxy ynamides,11b and the BF 3 ⋅OEt 2 ‐promoted intramolecular ring‐closing metathesis of ynamides bearing an aldehyde 12. In this report, we describe our results on a simple catalytic process that transforms aromatic 5‐enynamides, in the presence of a catalytic amount of InX 3 (X=OTf or Br), into nitrogen‐containing bi‐ and tricycles.…”

In Silico Design, Synthesis, and Biological Evaluation of Anticancer Arylsulfonamide Endowed with Anti-Telomerase Activity

“…For the preparation of sulfonamide compounds of type 1 and 2 (Figure 3), several procedures are present in the literature [54][55][56][57][58][59][60][61], and a few of them were also proposed recently in light of using more environmentally friendly green chemistry approaches [62][63][64][65][66].…”