153259-19-9Relevant academic research and scientific papers
The behavior of 4-triphenylmethyl-1,2-benzoquinone towards alkoxycarbonylmethylene(triphenyl)phosphoranes and triphenylphosphine in acetic anhydride
Osman, Fayez H.,El-Samahy, Fatma A.
, p. 21 - 30 (2007/10/03)
The reaction of alkoxycarbonylmethylene(triphenyl)phosphoranes (2) with 4-triphenylmethyl-1,2-benzoquinone (1) in acetic anhydride at room temperature for 7 h led to the formation of alkyl (6-acetoxy-α,α,α-triphenyl-m-tolyl)fumarates (7), alkyl (6-acetoxy-α,α,α-triphenyl-m-tolyl)maleates (8), benzofuran derivatives (13 and 14), 3,4-diacetoxytetraphenylmethane (18) along with triphenylphosphine and triphenylphosphine oxide. The action of alcoholic HCl on the fumarates 7 give the coumarin derivatives (19) whereas the maleates 8 yielded 19 and two additional products, alkyl (6-hydroxy-α,α,α-triphenylm-tolyl)maleates (6) and (E)-5-triphenylmethyl-3-alkoxycarbonylmethylenebenzo[b]furan-2(3H)-ones (20). Methylation of the products 6 with methyl iodide in dry acetone and anhydrous potassium carbonate gave the corresponding methyl ethers 21. When the maleates 6 were heated in boiling toluene for about 30 h, a mixture of the coumarin derivatives 19 and (Z)-isomer of 20 was obtained. Triphenylphosphine reacted with quinone 1 in acetic anhydride to give quantitative yield of 18 with triphenylphosphine oxide. Possible reaction mechanisms are considered.
Reaction of phosphonium ylides with 4-triphenylmethyl-1,2-benzoquinone
Osman, Fayez H.,Abd El-Rahman, Naglaa M.,El-Samahy, Fatma A.
, p. 8691 - 8704 (2007/10/02)
The reaction of alkoxycarbonylmethylene(triphenyl)phosphoranes (4) with 4-triphenylmethyl-1,2-benzoquinone (1) in dry benzene at room temperature for 3 h led to the formation of a novel type of compounds 7 along with triphenylphosphine oxide. When compounds 7 were allowed to reflux in boiling toluene for 5 h, a mixture of 4-alkoxycarbonyl-6-triphenylmethyl-2H-1-benzopyran-2-ones (11), 5-triphenylmethyl-3-alkoxycarbonylmethylene-benzo[b]furan-2(3H)-ones (12) and triphenylphosphine were obtained. The double bond moiety of the pyrone ring in 11 was reduced with zinc dust in boiling acetic acid to form 4-alkoxycarbonyl-6-triphenylmethyl-3,4-dihydro-2H-1-benzopyran-2-ones (13) in quantitative yields. Carrying out the reduction of 11 in presence of methanol yields the succinate derivatives 14, which upon methylation with methyl iodide in dry acetone and anhydrous potassium carbonate gave the corresponding methyl ethers 15. The reaction mechanisms are considered and the structural assignments of the new compounds are based on chemical and spectroscopic evidence.
