Applied Catalysis A: General 478 (2014) 138–145 Contents lists available at ScienceDirect Applied Catalysis A: General jou rn al hom epage: www.elsevier.com/locate/apcata Metathesis of cardanol over Ru catalysts supported on mesoporous molecular sieve SBA-15 Tushar Shinde, Vojtech Varga, Miroslav Polᡠsek, Michal Horᡠcek, Nadˇ eˇ zda ˇ Zilková, Hynek Balcar ∗ J. Heyrovsk´ y Institute of Physical Chemistry, v.v.i., Academy of Sciences of the Czech Republic, Dolejˇ skova 3, 182 23 Prague 8, Czech Republic a r t i c l e i n f o Article history: Received 3 February 2014 Received in revised form 26 March 2014 Accepted 27 March 2014 Available online 4 April 2014 Keywords: Cardanol Metathesis Supported catalysts Ru carbenes SBA-15 a b s t r a c t The Hoveyda–Grubbs type Zhan catalysts (ZC) and Grubbs second generation catalyst (GII) were immo- bilized on SBA-15 mesoporous molecular sieve by non-covalent interactions and phosphine linkers, respectively. Both hybrid catalysts proved to be highly active and selective in cardanol metathesis and cardanol cross-metathesis with ethene and cis-1,4-diacetoxy-2-butene (DAB). GII/SBA-15 was less active than ZC/SBA-15, however, Ru leaching was significantly lower for GII/SBA-15 (0.5%) than for ZC/SBA-15 (2.5%). In ethenolysis of cardanol, 3-(non-8-enyl)phenol was isolated as a major product. In cross- metathesis with DAB 9-(3-hydroxyphenyl)non-2-enyl acetate and non-2-enyl acetate were formed with high selectivity. Easy catalyst–product separation and low Ru leaching provide the products (applicable as detergent precursors and fragrance and flavor agents) free from the catalyst residue. © 2014 Elsevier B.V. All rights reserved. 1. Introduction In recent years cardanol has attracted a lot of attention in both academic as well as applied research [1–11]. Cardanol is a mixture of phenolic compounds manufactured from cashew nut shell liq- uid (CNSL), along with cardol and 2-methyl cardol (Fig. 1). Cardanol can be separated from other components of CNSL by double vac- uum distillation (at 400–500 Pa), in which the fraction boiling at 220 ± 15 ◦ C was collected as a clear to pale yellow liquid [10]. Com- ponents of cardanol are phenols having long hydrocarbon chain in meta position [3,5,6] which has one, two or three double bonds separated by one methylene group (mainly cis stereoisomers). The degree of unsaturation of cardanol depends upon the area of CNSL origin and also on the cardanol isolation and purification process [12]. Cardanol has gained a lot of importance: it serves as an excel- lent material for the preparation of high grade insulating varnishes, paints, resins, surface coating, frictional materials and surfactants. Nevertheless, because of still increasing CNSL production in the world (especially in Asia and Africa), development of new indus- trial applications of cardanol is highly desirable. From chemical point of view cardanol represents a renewable source of phenols [10,13,14]. Replacement of petroleum based sources of phenols ∗ Corresponding author. Tel.: +420 266053706; fax: +420 286582307. E-mail address: balcar@jh-inst.cas.cz (H. Balcar). by renewable plant-based ones is in accord with modern trends focused on global sustainability. Moreover cardanol is expected to be a low cost source of phenols because CNSL is practically a waste material. Olefin metathesis, one of the most exciting modern synthetic methods in organic chemistry [15], has been applied in synthesis and upgrading of many natural products including vegetable oils [16,17]. Many natural products having long unsaturated chains in molecules (natural rubber, carotene, squalene) have been trans- formed by cross-metathesis with ethene (ethenolysis) [18–20]. Similary, metathesis can transform unsaturated components of cardanol into long chain unsaturated hydrocarbons and valuable phenolic compounds. However, only a few papers have been reported on cardanol metathesis till now. Using homogeneous Hoveyda–Grubbs metathesis catalysts syntheses of bispheno- lic derivatives, cardanol based phorphyrins and cardanol based fulleropyrrolidines were described [3,4,9,11]. In addition, metathe- sis of cardanol leading to the synthesis of biologically active compounds (kairomones) was reported [21]. However, the poten- tial of cardanol metathesis as a source of fine chemicals is much larger. The main problems connected with metathesis in car- danol transformation seem to be in (a) difficult separation of individual cardanol components [3,13,21] urging to use a raw mixture for metathesis, and (b) the application of homogeneous Ru catalysts in relatively high amounts (1–5 mol% in most cases) without possibility of facile catalyst separation from the prod- ucts. http://dx.doi.org/10.1016/j.apcata.2014.03.036 0926-860X/© 2014 Elsevier B.V. All rights reserved.