Photocatalysis, the use of light to promote organic transformations, is a field of catalysis that has received limited attention despite existing for over 100 years. With the revolution of photoredox catalysis in 2008, the rebirth or awakening of the field of photoorganocatalysis has brought new ideas and reactions to organic synthesis. This review will focus on the sudden outburst of literature regarding the use of small organic molecules as photocatalysts after 2013. In particular, it will focus on acridinium salts, benzophenones, pyrylium salts, thioxanthone derivatives, phenylglyoxylic acid, BODIPYs, flavin derivatives, and classes of organic molecules as catalysts for the photocatalytic generation of C-C and C-X bonds.

An iodine-catalyzed Ritter-type amination of nonactivated C–H bonds is presented enabling the formation of 1,3-α-tertiary diamines. A sulfamidyl radical serves as the promoter in a guided tertiary C–H iodination through an exclusive 1,6-HAT process. The subsequent Ritter reaction furnishes the C–N bond and establishes an unprecedented concept for catalyst turnover in iodine redox catalysis. The general robustness of the methodology, including broad functional group tolerance, was demonstrated for 24 different 1,3-diamine derivatives, which were synthesized in yields of 42%–99%.

The covalent functionalization of MoS 2 with ap erylenediimide (PDI) is reported and the study is accompanied by detailed characterization of the newly prepared MoS 2-PDI hybrid material. Covalently functionalizedM oS 2 interfacing organic photoactive species has shown electron and/or energy accepting,energy reflecting or bi-directional electron accepting features.H erein, ar ationally designed PDI, unsubstituted at the perylene core to act as electron acceptor,f orces MoS 2 to fully demonstrate for the first time its electron donor capabilities.The photophysical response of MoS 2-PDI is visualized in an energy-level diagram, while femtosecond transient absorption studies disclose the formation of MoS 2 C +-PDIC À charge separated state.T he tunable electronic properties of MoS 2 ,a saresult of covalently linking photoactive organic species with precise characteristics,u nlock their potentiality and enable their application in light-harvesting and optoelectronic devices.

Supporting Information. Experimental procedures, synthetic route and characterization data. This material is available free of charge via the Internet at http://pubs.acs.org.

We successfully functionalized MoS2 and WS2 with Zn-porphyrin through 1,2-dithiolane addition. This creates mixed 0–2 dimensional materials since porphyrins are discrete on the basal plane of TMDs. This localization results in a new emission band with a 3.5 ns lifetime at 77.5 K with an excitation power of 17 W/cm2 in the near-infrared (NIR) region (1.40–1.51 eV), which originates from charge-separated states between ZnP and WS2. The optical response of excitonic species, including trion, biexcitons, and excitons, is substantially enhanced at the porphyrin absorption region, supporting electron transfer between ZnP and WS2. Sensing time-response improves after functionalization, suggesting that electrons injected from ZnP to TMDs contribute to filling trap states. Incorporating ZnP also enhances the stability of WS2 and MoS2 against atmospheric photodegradation. Theoretical modeling supports these findings, suggesting an intimate relationship between orbitals in the ground and excited states of porphyrin and TMDs.