Tris-N-(N′,N′,N″,N″-tetramethylguanidyl)phosphine Oxide – Synthesis and Reaction with Acids

Abstract

The phosphoryl compound (O:)P(TMG)3 (TMG = N’,N’,N”,N”-tetramethylguanidyl) (6) was synthesized during attempts to obtain the potentially very basic (but still unknown) compound P(TMG)3 (1). Its reaction with HCl resulted in the triply protonated species 7. The crystal structure of compound 7 was determined; it crystallizes as a bis-dichloromethane solvate. Each protonated nitrogen forms a hydrogen bond to one chloride. A series of protonation experiments was conducted in order to test the behaviour of 6 towards weak acids.

Experimental Basicities of Superbasic Phosphonium Ylides and Phosphazenes

“…In the reaction between P­(pyrr) 2 Cl or P­(dma) 2 Cl and TMG and also between P­(pyrr)­Cl 2 or P­(dma)­Cl 2 and TMG, the same products, that is, P­(pyrr) 2 tmg and P­(dma) 2 tmg, were obtained, respectively. It seems to be due to the disproportionation of already formed compounds on the reaction and/or distillation. , …”

“…It seems to be due to the disproportionation of already formed compounds on the reaction and/or distillation. 53,54 Phosphonium salts were synthesized according to eq 12: 41,55…”

Tris(tetramethylguanidinyl)phosphine: The Simplest Non‐ionic Phosphorus Superbase and Strongly Donating Phosphine Ligand

“…by more than 12 kcal/mol [24] . Schmutzler and co‐workers attempted to synthesize P(tmg) 3 via several reaction pathways, noting that the phosphine should possess extraordinary basicity [25–28] . Although they succeeded in isolating the P‐protonated form, the free phosphine P(tmg) 3 could not be liberated.…”

Database analysis of hydrogen bond patterns in phosphoric triamides completed with seven new compounds: a crystallographic and15N NMR study

“…Refcodes GAFJON63 and GAHGED64 offer two tri-phospha-cyclic structures (cyclo-tri-phosphazene like) with complicated patterns of hydrogen bonds, especially in the case of GAHGED where the structure includes twosymmetrically/crystallographically independent components for each of the species making this structure (cation, anion and solvated molecule). The P(O)[NHC(NMe 2 ) 2 ] 3 Cl 3 •2CH 2 Cl 2 salt (EZAPIE65 ) is an example of a compound with three H-atom donor sites versus many H-atom acceptor sites but with a simple hydrogen bond pattern as each N-H unit is hydrogen bonded only to one Cl − anion.Compounds with a PIJO)ijNIJC)IJC)]3 segment. The CSD search for the P(O)[N] 3 motif reveals some structures containing N-H or O-H groups in the organic part attached to the nitrogen atom which take part in hydrogen bonding, for example [C 6 H 10 (NCH 3 ) 2 ]P(O)[N(CH 3 )CH(C 6 H 5 )C(OH)(C 6 H 5 ) 2 ] (BOGKAJ 66 ) for the P(O)[N(C)(C)] 3 segment and/or [( i Pr) 2 N] 2 P(O)[NC(NH 2 )Ph] (TAHWOO 67 ) and P(O)[N(CH 3 )(NH 2 )] 3 (JAQMUK 68 ) including the P(O)[N(N)(C)] part.…”