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The underlying mechanism of the ongoing seismic swarm in the Noto Peninsula, Japan, which generates earthquakes at 10 times the average regional rate, remains elusive. We capture the evolution of the subsurface stress state by monitoring changes in seismic wave velocities over an 11-year period. A sustained long-term increase in seismic velocity that is seasonally modulated drops before the earthquake swarm. We use a three-dimensional hydromechanical model to quantify environmentally driven variations in excess pore pressure, revealing its crucial role in governing the seasonal modulation with a stress sensitivity of 6 × 10⁻⁹per pascal. The decrease in seismic velocity aligns with vertical surface uplift, suggesting potential fluid migration from a high–pore pressure zone at depth. Stress changes induced by abnormally intense snow falls contribute to initiating the swarm through subsequent perturbations to crustal pore pressure. 

Abstract Chemo-switchable catalytic [2+2+2] cycloaddition of alkenes with formaldimines is reported. Bis(tosylamido)methane (BTM) and 1,2-ditosyl-1,2-diazetidine (DTD), two bench-stable precursors for highly reactive tosylformaldimine, have been identified to be effective. BTM worked as a selective releaser of the formaldimine for catalytic [2+2+2] reactions toward hexahydropyrimidine products via a presumable ‘imine–alkene–imine’ addition. A unique catalytic retro-[2+2] reaction of DTD was used and has enabled a proposed ‘imine–alkene–alkene’ pathway with high chemoselectivity for the synthesis of 2,4-di­arylpiperidine derivatives. The two alternative processes are catalyzed by the simple and environmentally benign catalysts InCl3 and FeBr2, respectively. 

Abstract Ligand‐controlled regiodivergence has been developed for catalytic semireduction of allenamides with excellent chemo‐ and stereocontrol. This system also provides an example of catalytic regiodivergent semireduction of allenes for the first time. The divergence of the semireduction is enabled by ligand switch with the same palladium pre‐catalyst under operationally simple and mild conditions. Monodentate ligand XPhos exclusively promotes selective 1,2‐semireduction to afford allylic amides, while bidentate ligand BINAP completely switched the regioselectivity to 2,3‐semireduction, producing (E)‐enamide derivatives.