Catalysis of linear alkene metathesis by Grubbs-type ruthenium alkylidene complexes containing hemilabile α,α-diphenyl-(monosubstituted-pyridin-2-yl)methanolato ligands

• Tegene T. Tole,
• Johan H. L. Jordaan and
• Hermanus C. M. Vosloo

Beilstein J. Org. Chem. 2019, 15, 194–209, doi:10.3762/bjoc.15.19

• -methoxypyridin-2-yl)methanolato] were synthesized and tested for their activity, stability and selectivity in the 1-octene metathesis reaction. Overall the precatalysts showed good activity and high stability for the metathesis of 1-octene at temperatures above 80 °C and up to 110 °C. Selectivities towards the

• precatalysts can be attributed to electronic and steric effects associated with the adjacent bulky phenyl groups. Keywords: Grubbs-type precatalyst; hemilabile; 1-octene metathesis; pyridinyl-alcoholato ligand; Introduction The alkene metathesis reaction is now well established as a powerful synthetic tool

• Grubbs 2-type (5) metal carbenes with pyridinyl alcoholato ligands for the 1-octene metathesis reaction (Figure 3) [10][11][12][13][14]. The incorporation of pyridinyl-alcoholato ligands in the Grubbs-type precatalysts has shown an increase in the thermal stability, activity and lifetime of the

MoO₃ on zeolites MCM-22, MCM-56 and 2D-MFI as catalysts for 1-octene metathesis

• Hynek Balcar,
• Martin Kubů,
• Naděžda Žilková and
• Mariya Shamzhy

Beilstein J. Org. Chem. 2018, 14, 2931–2939, doi:10.3762/bjoc.14.272

• conversion to tetradecene KC14 was low. MCM-56-based catalysts Conversion curves for the 1-octene metathesis over 6MoO3/MCM-56(13) under standard conditions are displayed in Figure 3. In spite of the 2D character of support the conversions over 6MoO3/MCM-56(13) were significantly lower in comparison with

• molybdenum oxide metathesis catalysts. The catalysts, prepared by thermal spreading of MoO3 and/or MoO2(acac)2 on these supports in NH4+ forms (6 wt % and/or 5 wt % of Mo) were tested in neat 1-octene metathesis under mild conditions (batch reactor, atmospheric pressure, 40 °C). The catalyst activity

• patterns of parent supports and catalysts used. Asterisk marks MoO3. Conversion vs time curves for 1-octene metathesis over 6MoO3/MCM-22(28) and 6MoO3/SBA-15. Neat 1-octene, 1-octene/Mo = 320, t = 40 °C. Conversion vs time curves for the 1-octene metathesis over 6MoO3/MCM-56(13). Neat 1-octene, 1-octene/Mo