The addition of P(O)-H bonds to internal alkenes has been accomplished under solvent-free conditions without the addition of a catalyst or radical initiator. Using a prototypical secondary phosphine oxide, a range of substrates including cinnamates, crotonates, coumarins, sulfones, and chalcones were successfully functionalized. Highly activated acceptors such as isopropylidenemalononitrile and ethyl 2-cyano-3-methyl-2-butenoate underwent the phospha-Michael reaction upon simple trituration of the reagents at room temperature, whereas less activated substrates such as ethyl cinnamate and methyl crotonate required heating (>150 °C) in a microwave reactor to achieve significant consumption of the starting alkenes. For the latter alkenes, a competing reaction involving disproportionation of the ditolylphosphine oxide into ditolylphosphinic acid and ditolylphosphine was observed at the high temperatures needed to promote the addition reaction.

Highly efficient transmetalation between gold phosphites and iodopalladium species is presented. In addition to successful transfer of cyclic and acyclic phosphites, studies involving P‐chiral substrates revealed that an initial protodeauration as well as the target transmetalation were both stereospecific, and that the overall process occurred with retention of configuration at phosphorus. Building on the mechanistic work, a catalytic approach to the synthesis of chiral P‐arylated nucleoside derivatives was developed. This chemistry has the potential to be easily adapted for the preparation of a diverse group of P‐chiral species.

SummaryA range of arylgold compounds have been synthesized and investigated as single-component catalysts for the hydrophenoxylation of unactivated internal alkynes. Both carbene and phosphine-ligated compounds were screened as part of this work, and the most efficient catalysts contained either JohnPhos or IPr/SIPr. Phenols bearing either electron-withdrawing or electron-donating groups were efficiently added using these catalysts. No silver salts, acids, or solvents were needed for the catalysis, and either microwave or conventional heating afforded moderate to excellent yields of the vinyl ethers.

No abstract

The Front Cover shows the generation and reactivity of configurationally stable P‐metallated nucleoside derivatives. The examples shown in this illustration were prepared through a series of stereospecific protodemetalation and transmetalation reactions. The aurated examples were successfully used as substrates in stereospecific base‐free P‐arylation reactions leading to functionalized nucleosides. The authors thank Barbara Stockland for the design of the cover. More information can be found in the https://doi.org/10.1002/ejoc.201800397