10.18453/rosdok_id00004760 Tönjes, Jan Günther Jan Günther Tönjes http://d-nb.info/gnd/120065160X https://orcid.org/0000-0002-3411-9881 Universität Rostock 2024 540 Chemistry & allied sciences 2024 en https://purl.uni-rostock.de/rosdok/id00004760 urn:nbn:de:gbv:28-rosdok_id00004760-8 P(III)/P(V) redox cycling catalysis avoids phosphine oxide waste in reactions by reducing it in situ using silanes as terminal reductants. New methods were developed. In a catalytic base-free Wittig (BFW) reaction highly substituted alkenes were formed using environmentally friendly PMHS. An intermediate of the BFW was scavenged with acyl chlorides. Activated alkenes could thus be converted to furans with an unusual substitution pattern. Alcohols and epoxides were converted stereospecifically in a catalytic Appel chlorination under low catalyst loading using small amounts of hexachloroacetone.