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A new, convenient, and efficient method for the synthesis of homoallylic aromatic thioethers was developed. The present method consists of the formation of arylthionium intermediates from aromatic dithioacetals, which are trapped by a π-nucleophile. Screening of diverse aromatic substrates, selected Lewis acids, and allylstannane and allylsilane were evaluated. The method was found suitable for the preparation of homoallylic aryl thioethers bearing electron donating o-and p-groups only, as substrates with electron withdrawing groups were found unreactive to this system. Keywords Aromatic dithioacetals • Allylation • Lewis acid • Homoallyl sulfides Addition of π-nucleophiles to Lewis acids (LA)-activated carbonyl compounds or oxonium cations is one of the fundamental methods of construction of a new carbon-carbon bond (Yamamoto and Asao 1993; Masse and Panek 1995; Marshall 1996). As such, in a highly regioselective manner, in case of chiral substrates or catalysts with strong asymmetric induction, it is possible to obtain relevant alcohols or homoallylic ethers which are applicative building blocks in the synthesis of natural and biologically active products (Yus et al. 2013). Allyl metal reagents used in such process are allylborons, allylstannanes, allylsilanes, allyl halides, allyl acetates, allylindium (Yus et al. 2013; Shen et al. 2013; Kaib et al. 2016), or allyl transition metal complexes (e.g., Pd and Pt) that feature η 1-allyl or η 3-allyl bonding mode, respectively (Sone et al. 1995). Introduction of allyl function to the organic compounds gives opportunity for further double-bond transformations such as ozonolysis, epoxidation, dihydroxylation, cycloaddition hydroformylation, and olefin metathesis.

Epoxydiazocines belong to the rare class of small V-shaped molecules, closely related to Tröger’s base. Due to their intriguing, unique structure, they could serve as molecular building blocks for supramolecular chemistry. An extensive review on their synthesis is contained in this article. Moreover, our recent findings devoted to efficient and easily scalable synthesis of fluorinated epoxy[1,5][b,f]diazocines through solvent-free base-catalyzed condensation of ortho-aminophenones is provided. The unique V-shaped structure was confirmed by X-ray crystal structure analysis. Furthermore, the rigidity of the epoxy­diazocine skeleton allowed for racemate separation and the configuration of enantiomers was established by combining quantum chemical calculations and chiroptical methods.1 Introduction2 Synthetic Efforts Towards Epoxydibenzo[b,f][1,5]diazocines3 Synthetic Efforts Towards Fluorinated Epoxydibenzo[b,f][1,5]diazocines4 Conclusion