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A visible‐light‐driven and room temperature photo‐Wolff‐Kischner reaction of sulfur ylides and N‐tosylhydrazones has been developed for the first time to provide modular access to alkene synthesis. The high functional group tolerance and broad substrate scope were demonstrated by more than 60 examples. Both E‐ and Z‐olefinic stereochemistry in the products could be controlled with excellent stereoselectivity. A series of mechanistic studies support that the reaction should proceed through a radical‐carbanion crossover pathway, specifically involving addition of photo‐generated sulfur ylide radical cations to N‐tosylhydrazones to form carbanions and subsequent Wolff‐Kischner process. [ABSTRACT FROM AUTHOR]

Abstract: A mutifunctional ruthenium‐based conjugate Ru‐BSe was designed and synthesized. The Ru complex with favorable bioimaging function was covalently linked with a cancer‐targeted molecule that could be effectively internalized by the tumor to realize enhanced theranostic effects. The pH‐response of the Ru conjugate in tumor acidic microenvironment causes ligand substitution and release of therapeutic complex. This activated complex remains inert to the reducing biomolecule‐glutathione and terminally locates in mitochondria, in which it triggers oxidative stress, and activates intrinsic apoptosis. Real‐time monitoring reveals that this Ru conjugate could selectively accumulate in tumor tissue in vivo, which significantly suppresses tumor progression and alleviate the damage to normal organs, realizing the precise cancer theranosis. [ABSTRACT FROM AUTHOR]

The methanol to olefins conversion over zeolite catalysts is a commercialized process to produce light olefins like ethene and propene but its mechanism is not well understood. We herein investigated the formation of ethene in the methanol to olefins reaction over the H-ZSM-5 zeolite. Three types of ethylcyclopentenyl carbocations, that is, the 1-methyl-3-ethylcyclopentenyl, the 1,4-dimethyl-3-ethylcyclopentenyl, and the 1,5-dimethyl-3-ethylcyclopentenyl cation were unambiguously identified under working conditions by both solid-state and liquid-state NMR spectroscopy as well as GC-MS analysis. These carbocations were found to be well correlated to ethene and lower methylbenzenes (xylene and trimethylbenzene). An aromatics-based paring route provides rationale for the transformation of lower methylbenzenes to ethene through ethylcyclopentenyl cations as the key hydrocarbon-pool intermediates. [ABSTRACT FROM AUTHOR]

Over zeolite H-ZSM-5, the aromatics-based hydrocarbon-pool mechanism of methanol-to-olefins (MTO) reaction was studied by GC-MS, solid-state NMR spectroscopy, and theoretical calculations. Isotopic-labeling experimental results demonstrated that polymethylbenzenes (MBs) are intimately correlated with the formation of olefin products in the initial stage. More importantly, three types of cyclopentenyl cations (1,3-dimethylcyclopentenyl, 1,2,3-trimethylcyclopentenyl, and 1,3,4-trimethylcyclopentenyl cations) and a pentamethylbenzenium ion were for the first time identified by solid-state NMR spectroscopy and DFT calculations under both co-feeding ([13C6]benzene and methanol) conditions and typical MTO working (feeding [13C]methanol alone) conditions. The comparable reactivity of the MBs (from xylene to tetramethylbenzene) and the carbocations (trimethylcyclopentenyl and pentamethylbenzium ions) in the MTO reaction was revealed by 13C-labeling experiments, evidencing that they work together through a paring mechanism to produce propene. The paring route in a full aromatics-based catalytic cycle was also supported by theoretical DFT calculations. [ABSTRACT FROM AUTHOR]

Born to dye: Five fluorescein analogues were synthesised (see scheme). One analogue was found to emit in the NIR region with a high quantum yield, excellent photostability and good permeability. Three derivatives were found to specifically stain mitochondria and one dye responds to thiols with a strong turn‐on NIR fluorescence signal and colorimetric change, in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Hydrocarbon ‐ pool chemistry plays a critical role in methanol ‐ to ‐ olefins reaction, but in ‐ depth understanding of the reaction pathway still remains a big challenge. Over archetype H ‐ ZSM ‐ 5 zeolite, the observation and identification of carbocations is reported under working conditions. A paring route for producing propene in an aromatic ‐ based catalytic cycle is described by connecting the polymethylbenzenes and the carbocations. For more details, see the Full Paper by J. Xu, F. Deng et al. on page^^12432^^ff. [ABSTRACT FROM AUTHOR]