Nylon intermediates from bio‐based levulinic acid

Use of ZrO2/SiO2 as solid acid catalyst in the ring‐opening of bio‐based γ‐valerolactone with methanol in the gas phase leads to mixtures of methyl 2‐, 3‐ and 4‐pentenoate (MP) in over 95% selectivity, containing a surprising 81% of M4P. This allows the application of a selective hydroformylation of this mixture in which M4P is converted into methyl 5‐formyl‐valerate (M5FV) with 90% selectivity and the other isomers remain unreacted. Reductive amination of M5FV and ring‐closure to caprolactam in excellent yield had been reported before. The remaining mixture of 2‐ and 3‐MP was subjected to an isomerising methoxycarbonylation to dimethyl adipate in 91% yield.

from A via a.sfakia on Inoreader http://bit.ly/2FvWE56