Single, double, and triple silver centers bound by a tetradentate N,P ligand

Silver coordination complexes of 2-(diphenylphosphinomethyl)aminopyridine with weakly interacting counterions

“…In our BPMP coordination studies with the tfa -ion, it was observed that the coordination of tfa -influences the formation of a structure unique from the structures isolated with the BF 4 -and 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 13 OTf -ions; this is also observed here [24,25]. Even though 2-pyridyl ligands are typically not capable of polymer formation due to the limited flexibility of the N pyridyl moiety, polymer structures are isolable when a counterion or solvent molecule coordinates to the metal center(s) preventing chelation [2,27,41].…”

“…When compared to the length of the box, the width of the box is much shorter at 4.050 Å (Ag2···Ag2B). The P···N intraligand distance (P1A···N2 = 4.7584(22) Å) for a unit of DPAP-2 is comparable to the previously published BPMP complexes [24,25]. This suggests that despite the absence of a methylene bridge in the aminopyridine functionality, DPAP-2 and BPMP have similar abilities with regard to flexibility.…”

“…In a more recent publication, it was observed that under similar reaction conditions, a mixture of DPAP-2 and the di-substituted amine products were isolated [29]. While we only observed mono-substituted DPAP-2 in the synthesis of our ligand with 2-aminopyridine, we previously attempted to synthesize a mono-substituted derivative of the BPMP ligands with 2-aminomethylpyridine and observed a mixture of mono-and di-substituted products [24,25].…”

“…The addition of one equivalent of 5,5'-dimethyl-2,2'-dipyridyl ( shorter (~0.15 Å) than those observed in the BPMP complexes previously mentioned, and this is attributed to the absence of four bulky phenyl groups in 1 [24,25]. When compared to the Pd(II)…”

“…Previously, we have focused on utilizing the previously published Mannich condensation reaction to synthesize (bis(diphenylphosphinomethyl))picolylamine (BPMP-2 and BPMP-3) ligands that featured a tertiary amine functionality and three methylene bridges (Figure 1a and b) [24,25]. Throughout literature, this method has proved to be a route in which a variety of P,N-ligands can be easily obtained [2,[26][27][28][29][30][31][32][33][34].…”