An efficient synthesis combining phosphorus dendrimers and 15-membered triolefinic azamacrocycles: towards the stabilization of platinum nanoparticles

Abstract

The synthesis of a new series of phosphorus-containing dendrimers bearing as terminal groups triazatriolefinic macrocycles is reported, from generation 1 (6 macrocycles) to generation 4 (48 macrocycles). These macrocycles are linked to the dendrimers through diazaphospholane moieties (5-membered rings). The complexation ability of these dendrimers and of a compound possessing a single macrocycle was tested towards Pt 2 (dba) 3 . A discrete complex could be isolated only in the case of the model compound, whereas the dendrimers afford highly branched networks of Pt(0) nanoparticles interweaved with the dendrimers.

15-Membered Azamacrocycles as Core and End Groups of Phosphorus Dendrimers

“…1 H NMR (250 MHz, CDCl 3 ): d = 1.24 (d,J = 6.7 Hz,144 H,), 1.26 (d,J = 6.7 Hz,72 H,2.90 (sept,J = 6.7 Hz,12 H,, 3. 12 H,17),96 H,16,17,22,25,26),4.10 (sept,J = 6.7 Hz,24 H,4.81 (br s,6 H,NH),42 H,23,24,27), 6.45 (d,J = 7.7 Hz,2 H,6.65 (m,12 H,78 H,5,8,9,10,12,13,20), 7. 21 (s, 24 H, H-30), 8.25 (s, 4 H, H-15).…”

“…1 H NMR (400 MHz, CDCl 3 ): d = 1. 23 (br t,J = 7.2 Hz,216 H,35),2.90 (m,24 H,32),3.23 (m,12 H,96 H,15,22,25,26),4.10 (m,24 H,4.65 (br s,12 H,NH),42 H,23,24,27),102 H,5,8,9,10,12,13,20,30),7.2 (m,12 H,. 13 Anal.…”

“…The solid was washed with a mixture of THF-pentane (1:10, 2 × 5 mL) and dried to afford 0.08 g (89%) of the imine 8-G 2 as a white solid, which was not purified further. 1 180 H,22,23,28,31,32),4.11 (m,48 H,12 H,NH),78 H,29,30,33), 6.44 (d,J = 10.3 Hz,6 H,, 6.62 (d,J = 7.25 Hz,18 H,192 H,5,8,9,10,12,13,15,18,19,26,36),8.25 (s,12 H,…”

Organophosphorus Chemistry for the Synthesis of Dendrimers

“…In another example, both Cl linked to the same P react with a single diamine, creating a diazaphospholane cycle. This cycle can be obtained from various macrocycles [ 55 ], or can be linked to a macrocycle that is able to complex Pd 0 [ 56 ] or Pt 0 [ 57 ], to create nanoparticles of these metals, and even to organize them in dendritic networks [ 58 ].…”

Phosphorus dendrimers functionalised with nitrogen ligands, for catalysis and biology

“…The second way to graft the triaza triolefinic macrocycles on the surface of dendrimers consisted in using both amines of the chain to react with the P(S)Cl 2 functions of the dendrimers, affording a five membered ring incorporating one phosphorus and two nitrogen atoms (Scheme 9, part b). 47 All generations from 1 to 4 have been synthesized, and then reacted with Pt 2 (dba) 3 , affording Pt nanoparticles in all cases. Surprisingly, supramolecular assemblies composed of dendrimers and of coalesced Pt nanoparticles were obtained, in the form of dendritic assemblies.…”