Heterogeneous bromination of alkenes using Bi(III) polybromide complexes as {Br<inf>2</inf>} source

© 2016 The Royal Society of Chemistry.A new polybromide Bi(iii) complex (PyH)3{[Bi2Br9](Br2)} was synthesized and characterized by XRD and other methods. This compound is able to act as a selective bromination agent towards various types of substituted alkenes

Heterogeneous bromination of alkenes using Bi(III) polybromide complexes as {Br<inf>2</inf>} source

© 2016 The Royal Society of Chemistry.A new polybromide Bi(iii) complex (PyH)3{[Bi2Br9](Br2)} was synthesized and characterized by XRD and other methods. This compound is able to act as a selective bromination agent towards various types of substituted alkenes

Heterogeneous bromination of alkenes using Bi(III) polybromide complexes as {Br<inf>2</inf>} source

© 2016 The Royal Society of Chemistry.A new polybromide Bi(iii) complex (PyH)3{[Bi2Br9](Br2)} was synthesized and characterized by XRD and other methods. This compound is able to act as a selective bromination agent towards various types of substituted alkenes

Heterogeneous bromination of alkenes using Bi(III) polybromide complexes as {Br<inf>2</inf>} source

© 2016 The Royal Society of Chemistry.A new polybromide Bi(iii) complex (PyH)3{[Bi2Br9](Br2)} was synthesized and characterized by XRD and other methods. This compound is able to act as a selective bromination agent towards various types of substituted alkenes

Heterogeneous bromination of alkenes using Bi(III) polybromide complexes as {Br<inf>2</inf>} source

© 2016 The Royal Society of Chemistry.A new polybromide Bi(iii) complex (PyH)3{[Bi2Br9](Br2)} was synthesized and characterized by XRD and other methods. This compound is able to act as a selective bromination agent towards various types of substituted alkenes

Aldehydes as Alkylating Agents for Ketones

Common and non‐toxic aldehydes are proposed as reagents for alkylation of ketones instead of carcinogenic alkyl halides. The developed reductive alkylation reaction proceeds in the presence of the commercially available ruthenium catalyst [(cymene)RuCl2]2 (as low as 250 ppm) and carbon monoxide as the reducing agent. The reaction works well for a broad substrate scope, including aromatic and aliphatic aldehydes and ketones. It can be carried out without a solvent and often gives nearly quantitative yields of the products. This straightforward and cost‐effective method is promising not only for laboratory application but also for industry, which produces carbon monoxide as a large‐scale waste product

Synthesis, structure, electrochemistry, and metal-atom dynamics of cyclopentadienyl ferracarboranes

A series of metallacarboranes, incorporating the CpFe fragment, were studied by electrochemical techniques, temperature-dependent Mössbauer effect (ME) spectroscopy, and X-ray diffraction. The compounds studied include the parent dicarbollide complex CpFeC2B9H11 (1) and its reduced form [1]-, the charge-compensated ferradicarbollides 1-Cp-4-L-1,2,3-FeC2B9H10 [L = SMe2 (2a), NMe3 (2b), py (2c)] and their methylated analogs 1-Cp-2,3-Me2-4-SMe2-1,2,3-FeC2B 9H8 (2d) and 1-Cp*-4-SMe2-1,2,3-FeC 2B9H10 (2e), the isomeric ferratricarbollides CpFeC3B8H11 (3a-c), and the amino-substituted derivative 1-Cp-12-tBuNH-1,2,4,12-FeC3B8H10 (3d). The ferradicarbollides 2a-e were synthesized by reactions of the charge-compensated dicarbollide anions [9-L-7,8-R2-7,8-C 2B9H8]- (R = H, Me) with [(C 5R5)-Fe(MeCN)3]+ cations. The structures of 1, [NMe3Ph][1], and 2b were investigated by X-ray diffraction. The ME spectroscopic study elucidated the relationship between the nature of the five-membered carborane face coordinated to the metal center and the hyperfine interaction parameters of the Fe atom. Temperature-dependent recoil-free fraction studies yielded the root-mean-square-amplitude-of-vibration (rmsav) of the metal atom over a wide temperature range, which proved to be in good agreement with cristallographic Ui,j data for 1 and 3a,b. Electrochemistry shows that the isomeric ferratricarbollides 3a-c undergo reversible oxidation to the corresponding FeIII derivatives at potential values higher, on average, by about 0.4 V than those of the charge-compensated complexes 2a-c and by about 0.8 V than that of the parent ferradicarbollide [1]-. This result indicates the strong electron-withdrawing ability of the extra carbon atom relative to that of the replaced boron atom. As a consequence of the shift of the HOMO-LUMO frontier orbitals to the high energy levels, the FeII/FeI reduction becomes accessible. © Wiley-VCH Verlag GmbH &amp; Co. KGaA, 2006

(Tetramethylcyclobutadiene)cobalt complexes with phosphacarborane ligands

Reactions of the 11-vertex phosphadicarbollide anions [10-R-7,8,9-PC 2B 8H 9] - (R = H (1a) and Cl (1b)) and [9-Cl-7,8,11-PC 2B 8H 9] - (7) with [Cb*Co(MeCN) 3]PF 6 or [Cb*Co(C 6H 6)]PF 6 (Cb* = C 4Me 4) give the expected cobaltaphosphadicarbollides 1-Cb*-5-R-1,2, 3,4-CoPC 2B 8H 9 (R = H (2a) and Cl (2b)) and 1-Cb*-4-Cl-1,2,3,6-CoPC 2B 8H 9 (5b), respectively. 2a rearranges to a mixture of 1-Cb*-1,2,4,5-CoPC 2B 8H 10 (4a) and 1-Cb*-1,2,3,6-CoPC 2B 8H 10 (5a) at 110°C and further to 1-Cb*-1,2,3,5-CoPC 2B 8H 10 (6a) at 160°C. Heating of the Cl-substituted derivative 2b at 65°C results in 1-Cb*-5-Cl-1,2,4,8-CoPC 2B 8H 9 (3b). Both 2b and 5b rearrange at 100°C, giving 1-Cb*-5-Cl-1,2,3,10-CoPC 2B 8H 9 (8b) as a main product. The observed rearrangement sequence of Cb*CoPC 2B 8H 10 isomers correlates well with the relative stabilities of their nonmethylated analogues estimated by DFT calculations. Reaction of the diphosphacarbollide anion [7,8,10-P 2CB 8H 9] - (11) with Cb*Co(CO) 2I at 160°C affords the nonrearranged complex 1-Cb°-1,2,3,5-CoP 2CB 8H 9 (12). The structures of 2a, 3b, and 4a were determined by X-ray diffraction. The electrochemical study revealed that phosphadicarbollide ligands are stronger acceptors compared with tricarbollide [C 3B 8H 11] - and charge-compensated dicarbollide [9-L-7,8-C 2B 9H 10] -. © 2006 American Chemical Society