Nylon Intermediates from Bio-Based Levulinic Acid.

Area of Science:

• Catalysis
• Green Chemistry
• Organic Synthesis

Background:

• Biobased γ-valerolactone (GVL) is a promising platform chemical derived from lignocellulosic biomass.
• Efficient conversion of GVL into high-value chemicals is crucial for sustainable chemical production.
• Existing methods for GVL ring-opening often yield complex mixtures or require harsh conditions.

Purpose of the Study:

• To develop a selective catalytic process for the gas-phase ring-opening of GVL with methanol.
• To investigate the subsequent selective functionalization of the resulting methyl pentenoate isomers.
• To establish a pathway for producing ϵ-caprolactam and dimethyl adipate from GVL.

Main Methods:

• Gas-phase catalytic ring-opening of GVL using ZrO2/SiO2 solid acid catalyst.
• Selective hydroformylation of methyl 4-pentenoate (M4P) to methyl 5-formyl-valerate (M5FV).
• Isomerizing methoxycarbonylation of methyl 2- and 3-pentenoates to dimethyl adipate.

Main Results:

• Over 95% selectivity for methyl pentenoates (MP) mixture, with 81% M4P, from GVL ring-opening.
• 90% selectivity for M5FV via selective hydroformylation of M4P.
• 91% yield of dimethyl adipate from the remaining MP isomers via isomerizing methoxycarbonylation.

Conclusions:

• The developed catalytic system enables efficient and selective conversion of GVL into valuable chemical intermediates.
• This process offers a sustainable route to precursors for nylon production (ϵ-caprolactam) and plasticizers (dimethyl adipate).
• The selective functionalization of specific isomers within the MP mixture highlights the potential for tailored chemical synthesis from biomass.