We report herein versatile, transition metal-free and additive-free (hetero)­aryl–aryl coupling reactions promoted by the oxidative electrocoupling of unsymmetrical tetra­(hetero)­arylborates (TABs) prepared from ligand-exchange reactions on potassium trifluoroarylborates. Exploiting the power of electrochemical oxidations, this method complements the existing organoboron toolbox. We demonstrate the broad scope, scalability, and robustness of this unconventional catalyst-free transformation, leading to functionalized biaryls and ultimately furnishing drug-like small molecules, as well as late stage derivatization of natural compounds. In addition, the observed selectivity of the oxidative coupling reaction is related to the electronic structure of the TABs through quantum-chemical calculations and experimental investigations.

A novel, one-step N-dehydrogenation of amides to enamides is reported. This reaction employs the unlikely combination of LiHMDS and triflic anhydride, which serves as both the electrophilic activator and the oxidant, and is characterized by its simple setup and broad substrate scope. The synthetic utility of the formed enamides was readily demonstrated in a range of downstream transformations.

A catalytic 1,1‐difunctionalization of unactivated olefins en route to sp3 bis‐organometallic B,B(Si)‐reagents is described. The protocol is characterized by exceptional reaction rates, mild conditions, wide scope, and exquisite selectivity pattern, constituting a new platform to access sp3 bis‐organometallics.

Since the nowadays used lead-based primary explosives, lead azide, picrate and styphnate suffer from various environmental and toxic issues, there is a great need for new green materials. Therefore, two highly promising lead-free primary explosives potassium 1-(N-nitramino)-5Htetrazolate (1, 1-KNAT) and potassium 2-(N-nitramino)-5Htetrazolate (2, 2-KNAT) have been synthesized and characterized. Both isomers show superior energetic performance, initiation capability and were comprehensively analyzed by low-temperature X-ray diffraction, IR, multinuclear NMR spectroscopy, elemental analysis, and DTA. Sensitivity determinations toward impact, friction, and electrostatic discharge revealed its highly powerful, but also sensitive character. In addition, their potential as lead-free primaries were evaluated in initiation tests of PETN or RDX filled detonators confirming their great suitability as lead-free primary explosives. Figure 7. A) and B) HN test of 1 and 2; C) and D) HP test of 1 and 2; E) Positive PETN (left) and RDX (right) initiation tests with 5 mg of compound 1 (bottom) and 2 (top).

An alternative and complementary transformation for the synthesis of aryl- and heteroaryl-substituted alkynes is presented that relies on a chemoselective electrocoupling process. Tetraorganoborate substrates were logically designed and simply accessed by transmetalations using readily or commercially available organotrifluoroborate salts.

Zweifel olefination is a catalyst-free reaction that serves alkene functionalization. While most methods employ commercially available boron pinacol esters, we have assembled a sequence in which the two partners of the formal coupling reaction are installed successively, starting from inexpensive boron alkoxides. The in situ formation of bisorganoborinates was accomplished by consecutive reaction of two different organometallic species. This single-pot procedure represents a great advancement in the generation of organoborinates and their involvement in C−C bond formation.

A combination of 10 % CoCl2 and 20 % 2,2′‐bipyridine ligands enables cross‐coupling of functionalized primary and secondary alkylzinc reagents with various (hetero)aryl halides. Couplings with 1,3‐ and 1,4‐substituted cycloalkylzinc reagents proceeded diastereoselectively leading to functionalized heterocycles with high diastereoselectivities of up to 98:2. Furthermore, alkynyl bromides react with primary and secondary alkylzinc reagents providing the alkylated alkynes.

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