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The reductive coupling of an N‐heterocyclic carbene (NHC) stabilized (dibromo)vinylborane yields a 1,2‐divinyldiborene, which, although isoelectronic to a 1,3,5‐triene, displays no extended π conjugation because of twisting of the C2B2C2 chain. While this divinyldiborene coordinates to copper(I) and platinum(0) in an η2‐B2 and η4‐C2B2 fashion, respectively, it undergoes a complex rearrangement to an η4‐1,3‐diborete upon complexation with nickel(0). [ABSTRACT FROM AUTHOR]

The reductive coupling of an N‐heterocyclic carbene (NHC) stabilized (dibromo)vinylborane yields a 1,2‐divinyldiborene, which, although isoelectronic to a 1,3,5‐triene, displays no extended π conjugation because of twisting of the C2B2C2 chain. While this divinyldiborene coordinates to copper(I) and platinum(0) in an η2‐B2 and η4‐C2B2 fashion, respectively, it undergoes a complex rearrangement to an η4‐1,3‐diborete upon complexation with nickel(0). [ABSTRACT FROM AUTHOR]

The oxoboryl complex trans-[(Cy3P)2BrPt(BO)] ( 2) reacts with the Group 13 Lewis acids EBr3 (E=Al, Ga, In) to form the 1:1 Lewis acid-base adducts trans-[(Cy3P)2BrPt(BOEBr3)] ( 6- 8). This reactivity can be extended by using two equivalents of the respective Lewis acid EBr3 (E=Al, Ga) to form the 2:1 Lewis acid-base adducts trans-[(Cy3P)2(Br3Al-Br)Pt(BOAlBr3)] ( 18) and trans-[(Cy3P)2(Br3Ga-Br)Pt(BOGaBr3)] ( 15). Another reactivity pattern was demonstrated by coordinating two oxoboryl complexes 2 to InBr3, forming the 1:2 Lewis acid-base adduct trans-[{(Cy3P)2BrPt(BO)}2InBr3] ( 20). It was also possible to functionalize the BO triple bond itself. Trimethylsilylisothiocyanate reacts with 2 in a 1,2-dipolar addition to form the boryl complex trans-[(Cy3P)2BrPt{B(NCS)(OSiMe3)}] ( 27). [ABSTRACT FROM AUTHOR]

Ambient-temperature photolysis of the aminoborylene complex [(OC)5CrBN(SiMe3)2] in the presence of a series of trans-bis(alkynyl)platinum(II) precursors of the type trans-[Pt(CCAr)2(PEt3)2] (Ar=Ph, p-C6H4OMe, and p-C6H4CF3) successfully leads to twofold transfer of the borylene moiety [ :BN(SiMe3)2] onto the alkyne functionalities. The alkynyl precursors and resultant bis(borirene)platinum(II) complexes formed are of the type trans-[Pt(B{N(SiMe3)2}CCAr)2(PEt3)2] (Ar=Ph, p-C6H4OMe, and p-C6H4CF3). These species have all been successfully characterized by NMR, IR, and UV/Vis spectroscopy as well as by elemental analysis. Single-crystal X-ray diffraction has verified that these trans-bis(borirene)platinum(II) complexes display coplanarity between the twin three-membered rings across the platinum core in the solid state and stand as the first examples of coplanar conformations of twin borirene systems. These complexes were modeled using density functional theory (DFT), providing information helpful in determining the ability of the transition metal core to interact with each individual borirene ring system and allowing for the observed coplanarity of these rings in the solid state. This proposed transition metal interaction with the twin borirene systems is manifested in the electronic characterization of these borirene species, which display divergent photophysical UV/Vis spectroscopic profiles compared to a previously published mono(borirene)platinum(II) complex. [ABSTRACT FROM AUTHOR]

We present the isolation of the first mononuclear dihalogermylene, and mono- and dinuclear stannylene complexes of transition metals. These exhibit exceptionally pyramidalized Group 14 centers. Additionally, removal of the halide substituents from the Ge/Sn atom was successfully performed in two ways, halide abstraction and reduction, leading to a variety of unusual structural motifs. [ABSTRACT FROM AUTHOR]

Invited for the cover of this issue is the group of Holger Braunschweig at the Julius-Maximilians-Universität Würzburg. The image depicts a 'fight' for coplanarity in platinum­ trans -bis(borirene) complexes. Read the full text of the article at . [ABSTRACT FROM AUTHOR]

Photolysis of an aminoborylene complex in the presence of trans ‐ bis(alkynyl)platinum(II) precursors of the type trans ‐ [Pt(CCAr)2(PEt3)2] leads to a series of bis(σC ‐ borirenyl) complexes of PtII. These complexes display coplanarity of the borirene rings in the solid state, making them the first examples of borirene coplanarity. For more details, see the Full Paper by H. Braunschweig et al. on page 2377 ff. [ABSTRACT FROM AUTHOR]