Supported Ru olefin metathesis catalysts via a thiolate tether

Area of Science:

• Organometallic Chemistry
• Catalysis
• Materials Science

Background:

• Thiolate-coordinated ruthenium alkylidene complexes are known for high Z-selectivity and stereoretentivity in olefin metathesis.
• Developing efficient heterogeneous catalysts is crucial for sustainable chemical synthesis.

Purpose of the Study:

• To immobilize prototype ruthenium alkylidenes onto hybrid mesostructured silica using a thiolate tether.
• To evaluate the catalytic performance, specifically Z-selectivity, of these supported catalysts in olefin metathesis.

Main Methods:

• Synthesis of thiolate-tethered ruthenium alkylidene complexes.
• Immobilization of these complexes onto mesoporous silica supports.
• Evaluation of the heterogeneous catalysts in olefin metathesis reactions.

Main Results:

• A methodology was developed for the facile immobilization of ruthenium alkylidenes onto silica via thiolate linkers.
• The preparation of analogous molecular complexes in solution proved challenging.
• The supported catalysts exhibited slightly higher Z-selectivity than their molecular analogues, despite using small thiolates.

Conclusions:

• The successful immobilization of ruthenium alkylidenes opens avenues for developing advanced heterogeneous catalysts.
• Further optimization with more sophisticated thiolate ligands could lead to highly active and selective supported olefin metathesis catalysts.