One-pot syntheses of blue-luminescent 4-aryl-1H-benzo[f]isoindole-1,3(2H)-diones by T3P^® activation of 3-arylpropiolic acids

Abstract

In situ activation of 3-arylpropiolic acids with T3P® (n-propylphosphonic acid anhydride) initiates a domino reaction furnishing 4-arylnaphtho[2,3-c]furan-1,3-diones in excellent yields. Upon employing these anhydrides as reactive intermediates blue-luminescent 4-aryl-1H-benzo[f]isoindole-1,3(2H)-diones are formed by consecutive pseudo three-component syntheses in a one-pot fashion. The Stokes shifts correlate excellently with the Hammett–Taft σR parameter indicating an extended degree of resonance stabilization in the vibrationally relaxed excited singlet state.

Intramolecular cyclization reactions of arylpropargyl amides of electron-deficient α,β-alkenyl carboxylates and related compounds

“…3 Some thermal reactions of substrates containing aryl alkynes as dienes gave intramolecular Diels–Alder adducts. 4 Intramolecular [4 + 2] cycloaddition reactions of aryl alkynes with bases such as DBU, TBD, or Triton-B via allenic intermediates as a diene moiety have also been reported. 5 However, relatively limited structures such as dialkynes have been used and only a few electron-deficient alkenes, which are effective dienophiles in Diels–Alder reactions, 6 have been used so far.…”

An Efficient Method for the Preparation of N-Formamides using Propylphosphonic Anhydride (T3P®)

“…10 For instance, T3P ® has been used in dehydration chemistry that involves the conversion of carboxylic acids and amides into nitriles as in the synthesis of alkenes, isonitriles, and substituted hetero-cycles. 11 More recently, convenient microwave-assisted T3P ® mediated one-pot pyrazolone 12 and 4-aryl-benzo-isoindole-dione 13 syntheses have been reported. However, there is no report of the synthesis of formamides using T3P ® .…”