Next Article in Journal
Design of Specific Acid-Base-Properties in CeO2-ZrO2-Mixed Oxides via Templating and Au Modification
Previous Article in Journal
In-Situ Deposition of Plasmonic Gold Nanotriangles and Nanoprisms onto Layered Hydroxides for Full-Range Photocatalytic Response towards the Selective Reduction of p-Nitrophenol
Open AccessReview

TiO2 Photocatalyzed C–H Bond Transformation for C–C Coupling Reactions

School of Science, Beijing Technology and Business University, Beijing 100048, China
Basic Experimental Center for Natural Science, University of Science and Technology Beijing, Beijing 100083, China
Key Laboratory of Photochemistry, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
Authors to whom correspondence should be addressed.
Catalysts 2018, 8(9), 355;
Received: 2 August 2018 / Revised: 18 August 2018 / Accepted: 18 August 2018 / Published: 27 August 2018
Fulfilling the direct inert C–H bond functionalization of raw materials that are earth-abundant and commercially available for the synthesis of diverse targeted organic compounds is very desirable and its implementation would mean a great reduction of the synthetic steps required for substrate prefunctionalization such as halogenation, borylation, and metalation. Successful C–H bond functionalization mainly resorts to homogeneous transition-metal catalysis, albeit sometimes suffering from poor catalyst reusability, nontrivial separation, and severe biotoxicity. TiO2 photocatalysis displays multifaceted advantages, such as strong oxidizing ability, high chemical stability and photostability, excellent reusability, and low biotoxicity. The chemical reactions started and delivered by TiO2 photocatalysts are well known to be widely used in photocatalytic water-splitting, organic pollutant degradation, and dye-sensitized solar cells. Recently, TiO2 photocatalysis has been demonstrated to possess the unanticipated ability to trigger the transformation of inert C–H bonds for C–C, C–N, C–O, and C–X bond formation under ultraviolet light, sunlight, and even visible-light irradiation at room temperature. A few important organic products, traditionally synthesized in harsh reaction conditions and with specially functionalized group substrates, are continuously reported to be realized by TiO2 photocatalysis with simple starting materials under very mild conditions. This prominent advantage—the capability of utilizing cheap and readily available compounds for highly selective synthesis without prefunctionalized reactants such as organic halides, boronates, silanes, etc.—is attributed to the overwhelmingly powerful photo-induced hole reactivity of TiO2 photocatalysis, which does not require an elevated reaction temperature as in conventional transition-metal catalysis. Such a reaction mechanism, under typically mild conditions, is apparently different from traditional transition-metal catalysis and beyond our insights into the driving forces that transform the C–H bond for C–C bond coupling reactions. This review gives a summary of the recent progress of TiO2 photocatalytic C–H bond activation for C–C coupling reactions and discusses some model examples, especially under visible-light irradiation. View Full-Text
Keywords: TiO2 photocatalysis; C–H bond functionalization; C–C bond coupling; free-radical addition; photo-induced electron transfer (PET) TiO2 photocatalysis; C–H bond functionalization; C–C bond coupling; free-radical addition; photo-induced electron transfer (PET)
Show Figures

Figure 1

MDPI and ACS Style

Wang, Y.; Liu, A.; Ma, D.; Li, S.; Lu, C.; Li, T.; Chen, C. TiO2 Photocatalyzed C–H Bond Transformation for C–C Coupling Reactions. Catalysts 2018, 8, 355.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map

Back to TopTop