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Structural conjugation greatly affects the optical and electronic properties of the COF photocatalyst. Herein, we show that 2D hydrazone COFs with either π-extended biphenyl (BPh–COF) or acetylene (AC–COF) frameworks demonstrated distinct charge transfer and photocatalytic performances. The two COFs show good crystallinity and decent porosity as their frameworks are enforced by intra/interlayers hydrogen bonding. However, computational and experimental data reveal that AC–COF managed broader visible-light absorption and narrower optical bandgaps and performed efficient photoinduced charge separation and transfer in comparison with BPh–COF, meaning that the ethynyl skeleton with enhanced planarity better improves the π-conjugation of the whole structure. As a result, AC–COF exhibited an ideal bandgap for rapid oxidative coupling of amines under visible-light irradiation. Furthermore, taking advantage of its better charge transfer properties, AC–COF demonstrated considerable enhanced product conversion and notable functional tolerance for metallaphotocatalytic C–O cross-coupling of a wide range of both aryl bromides and chlorides with alcohols. More importantly, besides being recoverable, AC–COF showcased the previously inaccessible etherification of dihaloarene. This report shows a facile approach for manipulating the structure–activity relationship and paves the way for the development of a COF photocatalyst for solar-to-chemical energy conversion.

In the past few decades, forest policies have caused changes in forest landscape and community lifescape in the study area of Walanae Forest Management Unit (KPH Walanae), South Sulawesi Province. This research aims to analyze forest policy dynamics and their impacts on landscape and lifescape dynamics. We quantify landscape dynamics using land use and land cover change and landscape metrics in interpreting remote sensing results of four data sets obtained in 1990, 2000, 2009, and 2016. Furthermore, we investigate lifescape dynamics using qualitative/quantitative description. We found a rapid land use change in forest landscapes within the past 26 years. A significant change showed that, in 1990–2000, the primary forest that changed into the secondary forest and shrubs has changed into dry land agriculture mix shrubs. The decreased area of the forest brought an increase in economic income for people on one side and large disturbances and forest fragmentation on the other. Various forest policies influenced the forest composition and cover but were insufficiently successful in protecting the natural forest. Results showed that several forest policies that considerably impact the landscape and lifescape conditions include forest land designation, industrial forest plantation, and restoration activities. The policies on establishing KPH and social forest program have not shown the maximum result on the landscape and lifescape improvements and, therefore, must be supported.

[1n]Paracyclophane has been known for nearly 40 years, but its derivatives and properties are understudied in comparison to those of other macrocyclic compounds. By the modification of pillar[5]arene, we successfully obtained five electron-rich pentagonal macrocycles (pseudo[n]-pillar[5]arenes, n= 1–4) with the decrease of substituted phenylenes one after another, achieving the partial derivatization of [15]paracyclophane skeleton at its phenylene sites. Pseudo[n]-pillar[5]arenes (P[n]P[5]s) served as a kind of macrocyclic host to form complexes with various guests, such as dinitriles, dihaloalkanes, and imidazolium salt, in a 1:1 host–guest stoichiometric ratio. The binding constants with the guest gradually reduce along the decrease of substituted phenylene segments from host P[1]P[5]to P[4]P[5]. It is worthy to note that P[n]P[5]scan adjust their conformations to the “pillar-like” shape effectively when binding with succinonitrile in the solid state.