26620-46-2

Upstream product

• 513-81-5 2,3-dimethyl-buta-1,3-diene 
• 141-05-9 Diethyl maleate 
• 4741-86-0 isopropylidenecyclopropane 
• 623-91-6 diethyl Fumarate 
• 76-09-5 2,3-dimethyl-2,3-butane diol 
• 7647-01-0 hydrogenchloride 
• 13303-36-1 4,5-dimethyl-cyclohex-4-ene-1r,2c-dicarboxylic acid-anhydride 

Downstream Products

• 69094-40-2 diethyl 4,5-dimethylphthalate 
• 26620-46-2 (1S,2S)-4,5-Dimethyl-cyclohex-4-ene-1,2-dicarboxylic acid diethyl ester 
• 5680-10-4 4,5-dimethylphthalic acid 
• 89-05-4 1,2,4,5-benzenetetracarboxylic acid 

Relevant academic research and scientific papers

Sustainable production of pyromellitic acid with pinacol and diethyl maleate

Herein, we report an unprecedented and sustainable route to synthesize pyromellitic acid (PMA), a monomer of polyimide, with pinacol and diethyl maleate which can be derived from lignocellulose. Analogously, a sustainable route to trimellitic acid (TMA) was also developed using pinacol and acrylate as the feedstocks.

A method of preparing 1,2,4,5-benzenetetracarboxylic acid or trimellitic acid from pinacol

The invention relates to a method of preparing 1,2,4,5-benzenetetracarboxylic acid or trimellitic acid from pinacol. The method includes a first step of selectively dehydrating the pinacol in an acid/ionic liquid catalytic system to generate 2,-3-dimethyl-1,3-butadiene; a second step of subjecting the 2,-3-dimethyl-1,3-butadiene and maleate or acrylate to a D-A cycloaddition/dehydrogenation tandemreaction to generate an aromatic ring product; and a third step of subjecting the aromatic ring product to hydrolysis and oxidation to prepare the 1,2,4,5-benzenetetracarboxylic acid or the trimellitic acid. The catalytic system adopted in the method is green, and can be recycled. The raw material is a biomass-based platform chemical, and is cheap and easily available. All reaction processes aresimple. The pinacol dehydration reaction, the dehydrogenation reaction of a D-A product and an oxidation reaction are high in activity and selectivity. The novel method for preparing the 1,2,4,5-benzenetetracarboxylic acid and the trimellitic acid which are fine chemicals from the pinacol that is a lignocelluloses based platform chemical is provided by the invention.

NICKEL(O)-KATALYSIERTE CYCLOADDITIONEN VON (DIORGANYLMETHYLEN)CYCLOPROPANEN MIT ELEKTRONENARMEN OLEFINEN

Cycloadditions of (diorganylmethylene)cyclopropanes (R = Ph; CH3) with electron-deficient olefins are catalyzed by trisarylphosphite - Ni(O)-compounds to give (diorganylmethylene)cyclopentane derivatives in high yields.