Fullerene Derivatives Incorporating Phosphoramidous Ylide and Phosphoramidate: Synthesis and Property

Abstract

The reaction of dimethyl acetylenedicarboxylate (DMAD) with C(60) in the presence of hexamethylphosphorous triamide (HMPT) or hexaethylphosphorus triamide (HEPT) results in fullerene derivatives incorporating HMPT or HEPT ylides. The ylide derivatives exhibit unusual electronic absorptions in the visible region (435-660 nm), likely due to the presence of the ylide moiety. Electrochemical studies revealed that the first reductive potential of these compounds was more negative relative to those of both C(60) (DeltaE = 130 mV) and a simple Bingel adduct (DeltaE = 90 mV). A phosphoramidate side product, which resulted from the addition of HMPT or HEPT to C(60) followed by hydrolysis, exhibited a featureless absorption spectrum in the visible region and a more negative first reductive potential (DeltaE = 70 mV) relative to that of C(60).

Phosphine Organocatalysis

“…Chuang observed a similar transformation when using more nucleophilic phosphines. 808 Furthermore, Yang reported an example of ylide formation when using Dy@C 82 . 809…”

“…In the presence of an olefin, cyclopropanation occurs across the π-system, leading to a stable phosphorane (Scheme ). Chuang observed a similar transformation when using more nucleophilic phosphines . Furthermore, Yang reported an example of ylide formation when using Dy@C 82 …”

Fullerenes

“…93 The incorporation of hexamethylphosphorous triamide or hexaethylphosphorus triamide moiety within C 60 fullerene derivatives was achieved and the derivatives were characterised using spectroscopic methods and electrochemistry. 94 C 60 hexaadducts bearing ten azides and two TMS-protected alkyne groups allowing the successive attachment of ten alkyne building blocks and two azide units through successive click reactions have been described. 95 An efficient method to introduce an imine group to a monoadduct of C 60 fullerene to produce a 1-imino-4-organo-C 60 fullerene has been achieved using nitriles and trimethylsilylmethyl triflate.…”

Phosphine‐Catalyzed Reactions with Unsaturated Carbonyl Compounds

“…Herein, the treatment of C 60 with electron‐deficient DMAD 97 in the presence of triarylphosphine achieved the cycloaddition functionalization of C 60 , resulting in phosphorus ylide 98 a (with a yield of up to 39%). In the presence of hexamethylphosphorus triamide (HMPT) or hexaethylphosphorus triamide (HEPT), this reaction provided not only a phosphorus ylide but also a side product containing a phosphoramidate group ( 98 b ; Scheme ) …”