TY - JOUR

T1 - Reduction of Menthone with Isopropanol in the Presence of Palladium on Sibunit (ICT-3-31)

AU - Philippov, A. A.

AU - Chibiryaev, A. M.

N1 - Publisher Copyright: © 2018, Pleiades Publishing, Ltd.

PY - 2018/10/1

Y1 - 2018/10/1

N2 - The catalytic properties of the industrial “palladium on sibunit” catalyst (ICT-3-31, 0.5 wt % Pd) were studied in the reduction of menthone into menthol. Menthone was reduced both at 250 and 350°C using isopropanol as an H-donor under the conditions of the hydrogen transfer reaction (HTR). For comparison, a noncatalytic reaction was performed under the same conditions. At 350°C the conversion of menthone was the same (61–62%) in the presence of the catalyst and without it. In the reaction with the catalyst, the selectivity on the desired product menthol decreased considerably (from 98% down to 23%), and the amount of the by-products increased (from 2 up to 77% based on changed menthone). When the temperature of the catalytic reaction was lowered to 250°C, the reduction selectivity increased to 42%, but the conversion of menthone decreased to 10%. All the products of menthone conversion were identified and pathways of their formation suggested. At 250–350°C the carbon support sibunit catalyzed the dehydration of menthone, which hindered the satisfactory yields of the target alcohol. Other side reactions catalyzed by ICT-3-31 were dehydrogenation into p-menthenes and their further aromatization resulted in the formation of substituted benzenes—p-cymene and thymol. ICT-3-31 can be effectively used in HTR, if more reactive organic substrates are involved in the reaction below 200–250°C or stronger H-donors are applied.

AB - The catalytic properties of the industrial “palladium on sibunit” catalyst (ICT-3-31, 0.5 wt % Pd) were studied in the reduction of menthone into menthol. Menthone was reduced both at 250 and 350°C using isopropanol as an H-donor under the conditions of the hydrogen transfer reaction (HTR). For comparison, a noncatalytic reaction was performed under the same conditions. At 350°C the conversion of menthone was the same (61–62%) in the presence of the catalyst and without it. In the reaction with the catalyst, the selectivity on the desired product menthol decreased considerably (from 98% down to 23%), and the amount of the by-products increased (from 2 up to 77% based on changed menthone). When the temperature of the catalytic reaction was lowered to 250°C, the reduction selectivity increased to 42%, but the conversion of menthone decreased to 10%. All the products of menthone conversion were identified and pathways of their formation suggested. At 250–350°C the carbon support sibunit catalyzed the dehydration of menthone, which hindered the satisfactory yields of the target alcohol. Other side reactions catalyzed by ICT-3-31 were dehydrogenation into p-menthenes and their further aromatization resulted in the formation of substituted benzenes—p-cymene and thymol. ICT-3-31 can be effectively used in HTR, if more reactive organic substrates are involved in the reaction below 200–250°C or stronger H-donors are applied.

KW - dehydration

KW - dehydrogenation

KW - hydrogen transfer reaction

KW - menthol

KW - menthone

KW - palladium on sibunit

KW - reduction of ketones

KW - TRANSFER HYDROGENATION

KW - STEREOSELECTIVE HYDROGENATION

KW - NANOPALLADIUM

KW - FUNCTIONALIZED MESOCELLULAR FOAM

KW - EFFICIENT

KW - CATALYSTS

UR - http://www.scopus.com/inward/record.url?scp=85060148710&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/26525554-32ad-3658-9c02-d747e1f983b3/

U2 - 10.1134/S2070050418040074

DO - 10.1134/S2070050418040074

M3 - Article

AN - SCOPUS:85060148710

VL - 10

SP - 294

EP - 300

JO - Catalysis in Industry

JF - Catalysis in Industry

SN - 2070-0504

IS - 4

ER -