5,20-Diphenyl-10,15-bis(p-tolyl)-21-selenaporphyrin and Its Nickel(II) Complexes¹

Abstract

The synthesis of a new monoheteroporphyrin, 5,20-diphenyl-10,15-bis(p-tolyl)-21-selenaporphyrin (SeDPDTPH), is reported. The 21-selenaporphyrin has been characterized by 1H NMR, 13C NMR, mass spectrometry, and UV−visible spectra and an X-ray structural analysis. The free base selenaporphyrin SeDPDTPH crystallizes in the monoclinic space group P21/n with a =19.848(3) Å, b = 8.8410(14) Å, c = 20.503(4) Å, β = 103.375(12)° at 125 K with Z = 4. Refinement of all 4577 unique reflections and 453 parameters yielded R 1 = 0.096 (based on F 2). The presence of selenium atom elongates the macrocycle along the N(1)−N(3) axis when compared to a regular porphyrin. The π delocalization pattern is altered in the selenophene moiety in relation to the free selenophene. SeDPDTPH undergoes a two-step proton addition in solution. Mono- and dication formation results in distortion of the planar 21-selenaporphyrin structure. The monocation structure is solvent dependent as shown by the 1H NMR titration experiments. Insertion of Ni(II) into 21-selenaporphyrin yields NiII(SeDPDTP)Cl (S = 1, μeff = 3.3 μB). The electronic spectrum of this complex is porphyrin-like with a strong Soret band at 433 nm. The 1H NMR spectra of the high-spin nickel(II) complexes of 21-selenaporphyrin have been recorded and assigned by means of the selective deuteration, line width considerations, and a 2D COSY experiment. The characteristic pattern of pyrrole (downfield) and selenophene (upfield) resonances has been established. Direct σ-π spin density transfer has been proposed to explain the upfield shift of the selenophene protons. Imidazole replaces the chloride ligand to form five- and six-coordinate complexes. The spectroscopic and chemical properties of NiII(SeDPDTP)Cl resemble those of nickel(II) complexes with 21-thiaporphyrin. To account for these similarities, we suggest that the selenophene moiety is bent out of the porphyrin plane in NiII(SeDPDTP)Cl. Such a geometry allows metal ion to interact with selenium of selenophene in a side-on fashion.

Reactivity of Silole within a Core‐Modified Porphyrin Environment: Synthesis of 21‐Silaphlorin and its Conversion to Carbacorrole

“…[5,[22][23][24][25][26] Once arylaldehyde was included in the condensation, 5,10,15,20-tetraaryl-21-heteroporphyrins were produced as well. [5,6,8,[26][27][28] In the course of a typical synthesis in analogy to the formation of N-confused tetraarylporphyrin, [12,13] Nconfused heteroporphyrins were accompanied by formation of heteroporphyrins. [20,21] The use of X-confused derivatives 2,4-bis(arylhydroxymethyl)heterocyclopentadiene instead of a regular counterpart afforded X-confused heteroporphy-A C H T U N G T R E N N U N G rins.…”

Reactions of Nickel(II) 2,21-Dimethyl-2-aza-21-carbaporphyrin with Phenyl Grignard Reagents, Phenyllithium, and n-Butyllithium

“…24,[31][32][33][34][35][36][37][38][39] The shift pattern of the carbaporphyrin equatorial ligand resembles that found for the [(2-NCH 3 -21-CH 3 CTPP)Ni II (py)] + species, generated by titration of (2-NCH 3 -21-CH 3 CTPP)Ni II Cl with pyridine, as shown in Figure 2 (toluene-d 8 , 223 K):…”

Vibrational analysis of Ni(II) complex with 4,12-ditolyl-16,24-diphenyl-3-thiaporphyrin (SDTDPPNi(II)Cl) and its isotopic labeled (61Ni(II), −d6, and −d10) derivatives

“…The synthesis of freebase SDTDPPH was carried out according to the previously reported procedure [18,19]. The addition of NiCl 2 in methanol solution to a ligand in chloroform solution gave the five-coordinate SDTDPPNi(II)Cl [19,15].…”

“…The addition of NiCl 2 in methanol solution to a ligand in chloroform solution gave the five-coordinate SDTDPPNi(II)Cl [19,15]. After 8 h of heating under reflux, the solution was cooled and the solvent was evaporated under vacuum.…”

“…, ν(C 46 -C 34 ) [7], ν(C 64 -C 17 ) [7], ν(C 60 -C 17 ) [7], δ(H 51 -C 46 -C 34 ) [5], δ(H 65 -C 64 -C 17 ) [ [11], δ(H 59 -C 49 -C 48 ) [18], δ(H 58 -C 48 -C 47 ) [10], δ(H 66 -C 63 -C 64 ) [11], δ(H 67 -C 62 -C 61 ) [18], δ(H 68 -C 61 -C 60 ) [10] 337-338 332 0 0 1183 δ(H 52 -C 50 -C 46 ) [11], δ(H 59 -C 49 -C 48 ) [19], δ(H 58 -C 48 -C 47 ) [10], δ(H 66 -C 63 -C 64 ) [11], δ(H 67 -C 62 -C 61 ) [19], δ(H 68 -C 61 -C 60 ) [10] 332 0 0 1155 1163 ν(C 10 -C 8 ) [8], ν(C 10 -C 7 ) [9], ν(C 8 -C 6 ) [8], δ(H 9 -C 8 -C 6 ) [5], δ(H 11 -C 10 -C 7 ) [ [9], ν(C 70 -C 72 ) [8], ν(C 41 -C 42 ) [8], ν(C 40 -C 44 ) [9], δ(H 77 -C 74 -C 72 ) [7], [9], ν(C 60 -C 61 ) [9], ν(C 47 -C 48 ) [9], ν(C 50 -C 46 ) [9], δ(H 59 -C 49 -C 48 ) [7], δ(H 67 -C 62 -C 61 ) [7] 242-248 133 1 0…”