Process for the selective ortho-alkylation of phenolic compounds

Claim 2

In a process for the selective alkylation of the ortho position of a phenolic compound of the formula ##STR2## wherein R 1 , R 2 , R 3 and R 4 independently represent hydrogen atoms or saturated aliphatic hydrocarbon radicals having from 1 to 4 carbon atoms, by the catalytic reaction of said phenolic compound with a saturated aliphatic alcohol having from 1 to 4 carbon atoms, in the vapor phase, the improvement which comprises reacting at a temperature of from 250° C. to 550° C. said phenolic compound with said alcohol in a molar ratio ranging from 1:1 to 1:15 in the presence of a catalyst containing chromium oxide and tin oxide and having a Cr:Sn atomic ratio of from 100:0.1 to 100:60.

Claim 3

A process as claimed in claim 1 wherein the Cr:Sn atomic ratio ranges from 100:1 to 100:20.

Claim 4

A process as claimed in claim 1 wherein the reaction is carried out at a temperature of from 300° C. to 550° C.

Claim 5

A process as claimed in claim 1 wherein said catalyst further includes iron oxide, the chromium oxide, the tin oxide and the iron oxide being present in such a proportion as to give a Cr:Sn:Fe atomic ratio ranging from 100:01:0.01 to 100:60:20.

Claim 6

A process as claimed in claim 4 wherein the Cr:Sn:Fe atomic ratio ranges from 100:1:0.1 to 100:20:10.

Claim 7

A process as claimed in claim 1 wherein the active substance of the catalyst consists essentially of chromium oxide, tin oxide, and sulfate radical.

Claim 8

A process as claimed in claim 6 wherein the chromium oxide, the tin oxide, and the sulfate radical are present in such a proportion as to give a Cr:Sn:S atomic ratio ranging from 100:0.1:0.25 to 100:60:20.

Claim 9

A process as claimed in claim 7 wherein the Cr:Sn:S atomic ratio ranges from 100:1:0.5 to 100:20:10.

Claim 10

A process as claimed in claim 6 wherein the reaction is carried out at a temperature of from 250° C. to 500° C.

Claim 11

A process as claimed in claim 1 wherein the active substance of the catalyst consist essentially of chromium oxide, tin oxide, iron oxide, and sulfate radical.

Claim 12

A process as claimed in claim 10 wherein the chromium oxide, the tin oxide, the iron oxide, and the sulfate radical are present in such a proportion as to give a Cr:Sn:Fe:S atomic ratio ranging from 100:0.1:0.01:0.25 to 100:60:20:20.

Claim 13

A process as claimed in claim 11 wherein the Cr:Sn:Fe:S atomic ratio ranges from 100:1:0.1:0.5 to 100:20:10:10.

Claim 14

A process as claimed in claim 12 wherein the reaction is carried out at a temperature of from 250° C. to 500° C.

Claim 15

A process for the selective alkylation of the ortho position of a phenolic compound of the formula ##STR3## where R 1 , R 2 , R 3 and R 4 independently represent hydrogen atoms or saturated aliphatic hydrocarbon radicals having from 1 to 4 carbon atoms, by reaction of said phenolic compound with a saturated aliphatic alcohol having from 1 to 4 carbon atoms, in the vapor phase, which comprises reacting the phenolic compound with the alcohol in a molar ratio ranging from 1:1 to 1:15 in the presence of a catalyst having an active substance selected from the group consisting of Cr 2 O 3 -SnO 2 of a Cr:Sn atomic ratio ranging from 100:0.1 to 100:60, Cr 2 O 3 -SnO 2 -Fe 2 O 3 of a Cr:Sn:Fe atomic ratio ranging from 100:0.1:0.01 to 100:60:20, Cr 2 O 3 -SnO 2 -SO 4 -- of a Cr:Sn:S atomic ratio ranging from 100:0.1:0.25 to 100:60:20 and Cr 2 O 3 -SnO 2 -Fe 2 O 3 -SO 4 -- of a Cr:Sn:Fe:S atomic ratio ranging from 100:0.1:0.01:0.25 to 100:60:20:20, at a temperature of from 250° C. to 550° C.

Claim 16

A process for the selective alkylation of the ortho position of a phenolic compound of the formula ##STR3## where R 1 , R 2 , R 3 and R 4 independently represent hydrogen atoms or saturated aliphatic hydrocarbon radicals having from 1 to 4 carbon atoms, by reaction of said phenolic compound with a saturated aliphatic alcohol having from 1 to 4 carbon atoms, in the vapor phase, which comprises reacting the phenolic compound with the alcohol in a molar ratio ranging from 1:1 to 1:15 in the presence of a catalyst having an active substance selected from the group consisting of Cr 2 O 3 -SnO 2 of a Cr:Sn atomic ratio ranging from 100:0.1 to 100:60, Cr 2 O 3 -SnO 2 -Fe 2 O 3 of a Cr:Sn:Fe atomic ratio ranging from 100:0.1:0.01 to 100:60:20, Cr 2 O 3 -SnO 2 -SO 4 -- of a Cr:Sn:S atomic ratio ranging from 100:0.1:0.25 to 100:60:20 and Cr 2 O 3 -SnO 2 -Fe 2 O 3 -SO 4 -- of a Cr:Sn:Fe:S atomic ratio ranging from 100:0.1:0.01:0.25 to 100:60:20:20, at a temperature of from 250° C. to 550° C.

Claim 17

A process as claimed in claim 14 wherein the mixture is diluted with an inert gas.

Claim 18

A process as claimed in claim 14 wherein the reaction is carried out in the presence of water.