1,2‐Diaza‐3,5‐diborolidine CH₂BR¹‐(NR²)₂‐BR¹: Potentielle Vorstufen zu cyclischen Diborylcarben‐Liganden

Abstract

The reaction of the aminohaloboranes (Me 2 N)(R)BX (1) (a: R = Ph, X = Cl; b: R = Me, X = Br; c: R = iPr, X = Cl) with the di-Grignard reagent (BrMg) 2 CH 2 in ethyl ether/benzene mixtures afforded the diborylmethanes [(Me 2 N)(R)B] 2 CH 2 (2) (a: R = Ph; b: R = Me; c: R = iPr), which were subsequently converted into the corresponding bis(chloroboryl)methanes [(Cl)(R)B] 2 CH 2 (3) (a: R = Ph; b: R = Me; c: R = iPr). Base-assisted cyclocondensation of 3a-c with 1,2-diisopropylhydrazine afforded 1,2-diisopropyl-1,2-diaza-3,5-diorgano-3,5-diborolidines (4) (a: R = Ph; b: R = Me; c: R = iPr). Derivative 4a was deprotonated by potassium bis(trimethylsilyl)amide to give (1,2diisopropyl-1,2-diaza-3,5-diphenyl-3,5-diborolidinyl)potassium (5).

Synthesis, Characterization, and Trapping of a Cyclic Diborylcarbene, an Electrophilic Carbene

“…The diborylcarbenoids 2 F and 2 Cl , possessing a five-membered ring skeleton of CB 2 N 2 , 56 were prepared from compound 3 following Scheme 1. 57 Single crystals for both 2 F and 2 Cl were obtained from tetrahydrofuran (THF)/hexane solutions at ambient temperature, and the structures were unambiguously determined using X-ray crystallography (Figure 2).…”

Synthesis and reactivity of PC(sp3)P-pincer iridium complexes bearing a diborylmethyl anion

“…The 1,2-diaza-3,5-diborolanyl ligand, CB 2 N 2 skeleton, has been previously studied in the coordination to group 1, 8 and 12 metals showing coordination modes from η 1 to η 5 . 13…”