A 3, 4-dimercapto-3-cyclobutene-1, 2-dione-chelated ruthenium carbene catalyst for Z-stereoretentive/stereoselective olefin metathesis. Issue 19 (17th April 2019)

• Record Type: Journal Article
• Authors: Wang, Tao; Xie, Qingxiao; Guo, Weijie; Wu, Shutao; Zhang, Huiqing; Wang, Jianhui; Wu, Botao
• Is Part Of: Dalton transactions. Volume 48:Issue 19(2019)
• Page Start: 6473
• Page End: 6483
• Publication Date: 2019-04-17
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c9dt01016e
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : A ruthenium carbene catalyst chelated with a 3, 4-dioxocyclobut-1-ene-1, 2-dithiolate ligand was synthesized and its molecular structure was determined by single-crystal X-ray diffraction. Abstract : A ruthenium carbene catalyst chelated with a 3, 4-dioxocyclobut-1-ene-1, 2-dithiolate ligand was synthesized and its molecular structure was determined by single-crystal X-ray diffraction. The Ru catalyst had excellent catalytic activity with high yields and good Z / E ratios for the ring opening metathesis polymerization (ROMP) of norbornene (yield: 96%/ Z / E : 86 : 14) and 1, 5-cyclooctadiene (yield: 86%/ Z / E : 91 : 9) and for ring opening cross metathesis (ROCM) reactions of norbornene/5-norbornene-2- exo, 3- exo -dimethanol with styrene (yields: 64%–92%/ Z / E : 97 : 3–98 : 2) or 4-fluorostyrene (yield: 46%–94%/ Z / E : 98 : 2). The catalyst also had high Z -stereoretentivity (91 : 9–98 : 2) for cross-metathesis (CM) reactions of terminal olefins with ( Z )-2-butene-1, 4-diol. More importantly, the catalyst had moderate Z -stereoselectivity for homometathesis reactions of terminal olefins giving cis -olefins as the major products ( Z / E ratios of 70 : 30–77 : 23). Like other Ru carbene complexes, the catalyst tolerates many different functional groups. The presented data, supported by DFT calculations, show that our catalyst, bearing a chelating 3, 4-dioxocyclobut-1-ene-1, 2-dithiolate ligand, exhibits higher stability towards air than Hoveyda's stereoretentive complex systems.