Nature CommunicationsElectrochemical and photocatalytic generation of cis-olefin-bridged carbodication for umpolung [4+1] cycloadditionHidenori MatsuyamaKaisei YokoyamaTakuma SatoMasahiro TeradaTienan Jin2026-02-02Full textDOI https://doi.org/10.1038/s41467-026-68836-z