Overcoming Thermodynamically Driven Retro‐Diels–Alder Reaction through a Cascade One‐Pot Process Exemplified for a Bio‐Based Platform Chemical

Abstract

AbstractIn this contribution, we describe a new approach to apply thermodynamically unfavored reactions in synthetic chemistry and to integrate them in cascade processes. By means of a new developed procedure for multi‐step one‐pot syntheses, we succeeded in nearly completely converting a thermodynamically labile Diels–Alder adduct, which strongly tends to react back, to the target product with high conversion of >99 % and in excellent yield by coupling with a rapid subsequent hydrogenation reaction. In detail, the process is based on the use of a rotating reaction vessel to form a thin product film of the thermodynamically labile Diels–Alder product from 2‐methylfuran and maleic acid anhydride (as two bio‐based raw materials), which then slowly dissolves into solution and is immediately converted by hydrogenation to the target product. Such a combination of Diels–Alder reaction and hydrogenation in a sequential one‐pot process without by‐product formation enables the efficient production of the product, which represents a valuable bio‐based platform chemical. In addition, this process concept generally opens a perspective for the integration of thermodynamically unfavorable reaction steps in multi‐step one‐pot cascade processes while obtaining the desired target products in high yields.