TY - JOUR
T1 - Aryloxy complexes and cyclometallated aryloxy alkylidene complexes of tungsten (VI). Application to the metathesis of functionalized olefins
AU - Lefebvre, Frédéric
AU - Leconte, Michel
AU - Pagano, Salvatore
AU - Mutch, Andrew
AU - Basset, Jean-Marie Maurice
PY - 1995/1/1
Y1 - 1995/1/1
N2 - In this review article, the synthesis of aryloxy complexes of tungsten with the general formula W(OAr)xCl6-x is described together with that of aryloxy (chloro)neopentylidene-tungsten complexes. The properties of these compounds in the metathesis of non-functionalized and functionalized olefins are reviewed. The aryloxy complexes of tungsten are good air-stable precursor catalysts when combined with organotin or -lead cocatalysts. In particular, depending on the cocatalyst and substituents on the aryloxide ligands, one can achieve either linear or cross-linked polydicyclopentadienes. One can also govern the induction period for the obtention of cross-linked polydicyclopentadiene, a phenomenon compatible with the requirements of the RIM processing. The cyclometallated neopentylidene tungsten complex 1 can be synthesized by two different routes, either from the W(OAr)2Cl4 (OAr = -O-2,6-C6H3Cl2 or -O-2,6-C6H3Ph2) precursor or from the Schrock carbyne W(CCMe3)(Cl3)(dme). In both cases, when OAr = O-2,6-C6H3Ph2, a metallation occurs by cleavage of the CH bond in one substituting phenyl group. Complex 1 is probably one of the most active and stereoselective catalysts for metathesis of cis- and trans-2-pentene (total retention of the configuration of the starting olefin). Similarly, it selectively transforms 1-methyl-norbornene to 100% cis, 100% headtail syndiotactic poly-1-methyl-norbornene. Complex 1 is also one of the most active catalysts for metathesis of functionalized olefins: with ethyl oleate 1 converts approximatively 250 equivalents of ethyl oleate into 9-octadecene and diethyl-9-octadecenedioate at 25°C. Compound 1 converts approximatively 100 equivalents of unsubstituted diallyl ether into the corresponding 2,5-dihydrofurane, and it (as well as the bicomponent catalysts) is able to realize metathesis of ω-unsaturated glucosides into the corresponding di-glucosides. It is also able to convert cyclic and acyclic double bonds with thio-ether functionalities to the corresponding polymer or cyclic products. For example, 1 converts diallyl sulphide or related compounds to the corresponding 2,5-dihydrothiophene derivatives. Similarly, phosphorus, silicon and tin diallyl derivatives can be transformed into the corresponding cyclic compound ECH2CHCHCH2, E = P, Si, Sn.
AB - In this review article, the synthesis of aryloxy complexes of tungsten with the general formula W(OAr)xCl6-x is described together with that of aryloxy (chloro)neopentylidene-tungsten complexes. The properties of these compounds in the metathesis of non-functionalized and functionalized olefins are reviewed. The aryloxy complexes of tungsten are good air-stable precursor catalysts when combined with organotin or -lead cocatalysts. In particular, depending on the cocatalyst and substituents on the aryloxide ligands, one can achieve either linear or cross-linked polydicyclopentadienes. One can also govern the induction period for the obtention of cross-linked polydicyclopentadiene, a phenomenon compatible with the requirements of the RIM processing. The cyclometallated neopentylidene tungsten complex 1 can be synthesized by two different routes, either from the W(OAr)2Cl4 (OAr = -O-2,6-C6H3Cl2 or -O-2,6-C6H3Ph2) precursor or from the Schrock carbyne W(CCMe3)(Cl3)(dme). In both cases, when OAr = O-2,6-C6H3Ph2, a metallation occurs by cleavage of the CH bond in one substituting phenyl group. Complex 1 is probably one of the most active and stereoselective catalysts for metathesis of cis- and trans-2-pentene (total retention of the configuration of the starting olefin). Similarly, it selectively transforms 1-methyl-norbornene to 100% cis, 100% headtail syndiotactic poly-1-methyl-norbornene. Complex 1 is also one of the most active catalysts for metathesis of functionalized olefins: with ethyl oleate 1 converts approximatively 250 equivalents of ethyl oleate into 9-octadecene and diethyl-9-octadecenedioate at 25°C. Compound 1 converts approximatively 100 equivalents of unsubstituted diallyl ether into the corresponding 2,5-dihydrofurane, and it (as well as the bicomponent catalysts) is able to realize metathesis of ω-unsaturated glucosides into the corresponding di-glucosides. It is also able to convert cyclic and acyclic double bonds with thio-ether functionalities to the corresponding polymer or cyclic products. For example, 1 converts diallyl sulphide or related compounds to the corresponding 2,5-dihydrothiophene derivatives. Similarly, phosphorus, silicon and tin diallyl derivatives can be transformed into the corresponding cyclic compound ECH2CHCHCH2, E = P, Si, Sn.
UR - http://www.scopus.com/inward/record.url?scp=0000665161&partnerID=8YFLogxK
U2 - 10.1016/0277-5387(95)85007-4
DO - 10.1016/0277-5387(95)85007-4
M3 - Article
AN - SCOPUS:0000665161
VL - 14
SP - 3209
EP - 3226
JO - Polyhedron
JF - Polyhedron
SN - 0277-5387
IS - 22
ER -