# US 2014/0235892 A1 · Process for the preparation of a benzene derivative > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0235892 A1 - Document ID: US20140235892A1 - Status: Published application - Kind: A1 - Application number: 14/346,380 - Filed: 2012-09-28 - Published: 2014-08-21 - Earliest claimed: 2011-09-30 - Assignees: Furanix Technologies B.V. - Applicants: Stichting Dienst Landbouwkunding Onderzoek; Furanix Technologies B.V. - Inventors: Matheus Adrianus Dam; Edserd de Jong; Jacco van Haveren; Alaiksai Pukin - Web page: https://patentgrep.com/patent/US20140235892A1 ## CPC - C07C 51/41: Preparation of salts of carboxylic acids ({C07C51/093 - C07C51/34 take precedence} preparation of soap C11D) - C07C 51/16: by oxidation (C07C51/145 takes precedence) - C07C 51/275: of hydrocarbyl groups - C07C 51/285: with peroxy-compounds - C07C 51/412: {by conversion of the acids, their salts, esters or anhydrides with the same carboxylic acid part} - C07D 307/42: Singly bound oxygen atoms - C07D 493/18: Bridged systems - C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS - C07D: HETEROCYCLIC COMPOUNDS (macromolecular compounds C08) ## Abstract A substituted benzene derivative is prepared in a process, which includes reacting a furan derivative of formula (I): wherein R is an alkyl group, with an olefin of formula (II): R1—CH═CH—R2 (II) wherein R1 and R2 are the same or different and independently are selected from the group consisting of hydrogen, —CN, —CHO and —COOR3, wherein R3 is selected from hydrogen or an alkyl group, or R1 and R2 together form a —C(O)—O—(O)C— group, with the proviso that R1 and R2 are not both hydrogen, to produce a bicyclic ether; and dehydrating the bicyclic ether to obtain a benzene derivative. The benzene derivative thus obtained can suitably be converted to a benzene carboxylic acid compound by oxidation. ## Claims ### Claim 1 A process for the preparation of a substituted benzene derivative, which comprises: reacting a furan derivative of formula (I): wherein R is an alkyl group, with an olefin of formula (II): R1—CH═CH—R2 (II) wherein R1 and R2 are the same or different and independently are selected from the group consisting of hydrogen, —CN, —CHO and —COOR3, wherein R3 is selected from hydrogen or an alkyl group, or R1 and R2 together form a —C(O)—O—(O)C— group, with the proviso that R1 and R2 are not both hydrogen, to produce a bicyclic ether; and dehydrating the bicyclic ether. ### Claim 2 (depends on 1) The process according to claim 1, wherein R is selected from an alkyl group containing from 1 to 6 carbon atoms. ### Claim 3 (depends on 1) The process according to claim 1, wherein the furan derivative of formula (I) has been obtained from the dehydration of a carbohydrate to yield furfural and the conversion of furfural thus obtained. ### Claim 4 (depends on 3) The process according to claim 3, wherein the carbohydrate is selected from a pentose. ### Claim 5 (depends on 3) The process according to claim 3, wherein the carbohydrate is selected from arabinose, ribose, ribulose, xylose, xylulose and lyxose. ### Claim 6 (depends on 1) The process according to claim 1, wherein the furan derivative of formula (I) has been obtained from the conversion of furfural that is formed during the dehydration of a hexose. ### Claim 7 (depends on 1) The process according to claim 1, preceding claims, wherein the furan derivative of formula (I) is reacted with the olefin of formula (II) at a temperature of from 0 to 150° C., preferably from 20 to 100° C. ### Claim 8 (depends on 1) The process according to claim 1, wherein a Lewis acid is used as a Diels-Alder catalyst. ### Claim 9 (depends on 1) The process according to claim 1, wherein the molar ratio between the amount of furan derivative of formula (I) to the amount of olefin of formula (II) ranges from 0.1:1 to 10:1, preferably from 0.5:1 to 2:1. ### Claim 10 (depends on 1) The process according to claim 1, wherein the bicyclic ether is dehydrated in the presence of a solvent. ### Claim 11 (depends on 10) The process according to claim 10, wherein the solvent is selected from the group consisting of alcohols, esters, ketones, amides, aldehydes, ethers, ionic liquids and sulphoxides, preferably alcohols. ### Claim 12 (depends on 10) The process according to claim 10, wherein the solvent is an aliphatic alcohol with 1 to 3 carbon atoms. ### Claim 13 (depends on 1) The process according to claim 1, wherein the bicyclic ether is dehydrated in the presence of a catalyst. ### Claim 14 (depends on 13) The process according to claim 13, wherein the catalyst is a basic catalyst. ### Claim 15 (depends on 13) The process according to claim 13, wherein the basic catalyst is selected from the group consisting of alkali metal hydroxides, alkanolates, carboxylates and carbonates, the catalyst preferably being alkali metal methanolate or ethanolate. ### Claim 16 (depends on 1) The process according to claim 1, wherein the bicyclic ether is dehydrated at a temperature in the range from −20 to 100° C. ### Claim 17 (depends on 1) The process according to claim 1, wherein the bicyclic ether is dehydrated at a pressure ranging from 0.5 to 50 bar. ### Claim 18 (depends on 1) The process according to claim 1, wherein bicyclic ether is dehydrated in a batch or continuous reactor wherein the residence time is from 0.1 to 48 hours. ### Claim 19 (depends on 1) The process according to claim 1 wherein the reaction of the furan derivative of formula (I) with the olefin of formula (II) and the dehydration reaction are performed in one step. ### Claim 20 (depends on 1) The process according to claim 1, wherein the benzene derivative produced by the dehydration of the bicyclic ether is oxidized. ### Claim 21 A process for the preparation of a benzene carboxylic acid compound comprising: reacting a furan derivative of formula (I): wherein R is an alkyl group, with an olefin of formula (II): R1—CH═CH—R2 (II) wherein R1 and R2 are the same or different and independently are selected from the group consisting of hydrogen, —CN, —CHO and —COOR3, wherein R3 is selected from hydrogen or an alkyl group, or R1 and R2 together form a —C(O)—O—(O)C— group, with the proviso that R1 and R2 are not both hydrogen, to produce a bicyclic ether; dehydrating the bicyclic ether to yield a benzene derivative; and oxidizing the benzene derivative thus obtained. ### Claim 22 (depends on 21) The process according to claim 21, wherein the oxidation is effected by an oxygen-containing gas in the presence of a catalyst comprising cobalt and manganese or by potassium permanganate or nitric acid. ### Claim 23 (depends on 22) The process according to claim 22, wherein the catalyst comprises cobalt and manganese, and further comprises bromine. ### Claim 24 (depends on 21) The process according to claim 21, wherein the oxidation is carried out at a temperature of from 60 to 220° C., at a pressure of from 5 to 100 bar and at a residence time of from 0.1 to 48 hours.