4′-(N-(Propan-1,2-dienyl)pyrrol-2-yl)-2,2′:6′,2″-terpyridine

Abstract

A new pyrrole-substituted terpyridine derivative that possesses an allene moiety was obtained as an “unexpected” sole product during an attempt to alkylate the N-atom of pyrrole with propargyl bromide in order to obtain an alkyne-functionalized terpyridine.

4′-(N-(Propargyl)pyrrol-2-yl)-2,2′:6′,2′′-terpyridine

“…Compound 1: 1 H-NMR (CDCl 3 , 400 MHz), δ (ppm): 8.71 (m, 2H H6, 6 ), 8.65 (d, 2H, H3, 3 , J = 8.0 Hz), 8.57 (s, 2H, H3 , 5 ), 7.87 (td, 2H, H4, 4 , J = 7.6 Hz, J = 1.8 Hz), 7.34 (ddd, 2H, H5, 5 , J = 7.5 Hz, J = 4.8 Hz, J = 1.1 Hz), 7.07 (dd, 1H, Hd, J = 2.7 Hz, J = 1.8 Hz), 6.62 (dd, 1H, Hb, J = 3.7 Hz, J = 1.8 Hz), 6.32 (dd, 1H, Hc, J = 3.7 Hz, J = 2.9 Hz), 4.91 (d, 2H, He, J = 2.6 Hz), 2.45 (t, 1H, Hg, J = 2.6 Hz). 13 Compound 2: The physical and spectroscopic properties agree with those reported in the literature [13].…”

“…The molecular structure of compound 1 was unambiguously confirmed by different analytical techniques. First, the 1 H-NMR spectrum (Supplementary Material) exhibits the typical signals for the terpyridine and pyrrole sub-units as reported for other pyrrole-terpys [6,13,14,22,23]. Moreover, the acetylenic protons were characterized by a triplet and a doublet (J = 2.6 Hz) centered at 2.45 and 4.91 ppm, respectively.…”

“…A tentative synthesis of 1 through N-propargylation of 4′-(pyrrol-2-yl)-2,2′:6′,2″-terpyridine is already reported in the literature [13]. The synthetic pathway that was…”

“…A tentative synthesis of 1 through N-propargylation of 4 -(pyrrol-2-yl)-2,2 :6 ,2terpyridine is already reported in the literature [13]. The synthetic pathway that was explored relies on the N-alkylation of the pyrrole ring with propargyl bromide in a strong basic medium [14].…”

Editorial: Special Issue “Molecules from Side Reactions”

“…In the twelfth paper, the authors reported on the synthesis of a new pyrrole-substituted terpyridine derivative that possessed an allene moiety. It was obtained as an unexpected sole product during attempts to alkylate the N-atom of pyrrole [13]. In the last paper, the serendipitous formation of the cyclic guanidinium complex poly[1,3-dimethyltetrahydropyrimidin-2(1H)-iminium [tri-µ 2 -cyanido-κ 6 C:N-dicuprate(I)]] was found during an X-ray analysis of the crystals obtained after an attempted synthesis of a copper cyanide polymer involving the diamine N,N -1,3-dimethyldiaminopropane [14].…”