Rhodium-mediated Assembly of New Heterocycles: From Borylenes to Oxaboroles.

Base-stabilized rhodium borylene complex κ-L(CO)Rh(BMes), 2; κ-L=κ-NN'-Rh,κ-N-B-(2,5-[PrP=N(4-PrCH)]-N'(CH)); Mes=mesityl, reacts with a series of alkynes (PhC≡C-R; R=Ph, Me, COEt, H) to yield unique structures whereby the alkyne has regioselectively added across boron and the carbon atom of a CO ligand. The resulting complexes, LRh[C(O)C(Ph)C(R)B(Mes)], 3, react with additional CO to afford cycle-containing products, L(CO)Rh ), 5, that ultimately release highly functionalized organic heterocycles of the form =NPipp (Pipp=4-PrCH), 6. These oxaboroles, which were assembled from a primary hydroborane, CO, an alkyne, and an azide-generated NPipp, are structurally analogous to two of the five boron-containing therapeutics approved by the FDA.

Mortality caused by tropical cyclones in the United States.

Natural disasters trigger complex chains of events within human societies. Immediate deaths and damage are directly observed after a disaster and are widely studied, but delayed downstream outcomes, indirectly caused by the disaster, are difficult to trace back to the initial event. Tropical cyclones (TCs)-that is, hurricanes and tropical storms-are widespread globally and have lasting economic impacts, but their full health impact remains unknown.

Mainstreaming nature in US federal policy.

Integrated policy changes must be cross-sectoral, appropriate, strategic, and evidence-based.

Rhodium-Mediated Dehydrogenation of Hydroboranes and Group 14 Compounds: Base-Stabilized Silylene and Germylene Complexes vs. Transmetalation.

Monocarbonyl rhodium complex LRh(CO), 1, which is stabilized by a pyrrole-based bis(phosphinimine) pincer ligand (L=κ -NNN'=2,5-[ Pr P=N(4- PrC H )] -N'(C H ) ), serves as a versatile platform for the dehydrogenation of group 14 substrates. Reaction with primary and secondary silanes and germanes (MesSiH , Et SiH , Ph GeH , BuGeH ; Mes=mesityl) liberates H and yields base-stabilized tetrylene compounds of the form κ -L(CO)Rh(ER ) (E=Si: R=Mes, H, 2; R=Et, 5; E=Ge: R=Ph, 6; R= Bu, H, 8). The ":ER " fragment in these species bridges between the rhodium center and a phosphinimine donor.

Harmonized nitrogen and phosphorus concentrations in the Mississippi/Atchafalaya River Basin from 1980 to 2018.

Water quality monitoring can inform policies that address pollution; however, inconsistent measurement and reporting practices render many observations incomparable across bodies of water, thereby impeding efforts to characterize spatial patterns and long-term trends in pollution. Here, we harmonized 9.2 million publicly available monitor readings from 226 distinct water monitoring authorities spanning the entirety of the Mississippi/Atchafalaya River Basin (MARB) in the United States.