Preparation of the Piperazine– and Triethylenediamine–Monoborane Adducts of BH₃, BH₂F, BHF₂, and BF₃

Abstract

J. M. VANPAASSCHEN and R. A. GEANANGEL. Can. J. Chem. 53.723 (1975). The new compounds, triethylenediamine-BH2F, -BHF2, -BFJ and piperazine-BH2F, -BHF2, -BFJ have been isolated and characterized from the base displacement reactions involving the diamine and the trimethylamine-fluoroboranes. By this method only the monoborane adducts of the difunctional amines are formed. The stability of these monoborane adducts is rationalized from a mechanistic point of view. The proton and boron-1 1 n.m.1. and i.r. spectraare presented with the analytical results.J. M. VANPAASSCHEN et R. A. GEANANGEL. Can. J. Chem. 53.723 (1975). On a isole et caractkrisk les nouveaux composes triethylknediamine-BH2F, -BHFz, -BFJ, piperazine-BHzF, -BHF2 et -BFJ; ces complexes sont obtenus en faisant reagir les diamines approprikes sur le complexe trimethylamine-fluoroborane. L'utilisation de cette methode conduit uniquement aux adduits du monoborane sur les amines difonctionnelles. On rationnalise la stabilite de ces adduits de monoboranc en se basant sur un point de vue mecanistique. En plusdes donnees analytiques, on rapporte les spectres r.m.n. du proton et du bore 11 e t les spectres i.r.[Traduit par le journal]

Access to NHC–Boryl Mono‐ and Bis‐Selenide and Utility as Mild Selenium Transfer Reagent Including to the C−F Bond

“…[24] The synthetic route to access BH 2 F is non-trivial because it involves the reaction of Lewis base stabilized BH 3 with anhydrous HF. [25] We envisaged in isolating NHC • BH 2 F in this stoichiometric reaction as a by-product, but it smoothly underwent ring expansion via the insertion of the B atom into the CÀ N bond of one NHC ligand to form a six membered BCNC 2 N ring. [26] The later can also be called a diazafluoroborinane derivative.…”

“…Another very interesting aspect of this C−F bond activation reaction was the concomitant ring expansion of the expected by‐product, NHC−BH 2 F. BH 2 F has been detected as a transient chemical species in the reaction of diborane with trifluoroborane by microwave spectroscopic technique [24] . The synthetic route to access BH 2 F is non‐trivial because it involves the reaction of Lewis base stabilized BH 3 with anhydrous HF [25] . We envisaged in isolating NHC ⋅ BH 2 F in this stoichiometric reaction as a by‐product, but it smoothly underwent ring expansion via the insertion of the B atom into the C−N bond of one NHC ligand to form a six membered BCNC 2 N ring [26] .…”

Molecular addition compounds. 5. Interaction of N,N,N',N',-tetramethylethylenediamine with boron trifluoride and monoalkylboranes

“…Treatment of the 1:1 addition compounds with an equimolar quantity of Et2OBF3 precipitates half of the TMED and forms the 1:2 complex in solution (eq 7). This reaction was used THF 2TMED-BH2R + 2Et2OBF3->- TMED-2BH2R + TMED-2BF3| (7) for the preparation of TMED*2BH2(IPC) (eq 8).…”

“…TMED-2BH2(IPC) (7). A solution of TMED.BH2(IPC) (10 mmol) in Et20 (10 mL) was taken in a 50-mL centrifuge vial and 1.23 mL of Et2OBF3 (10 mmol) was added to it with constant stirring.…”

Conformations of 1,3,3,5,7,7-Hexamethyl-1,5-diazacyclooctane and Its Bis-BH3 Adduct. Mono- and Bis-BH3 Adducts of Di-Tertiary Amines

“…It has been reported − that tetramethylethylenediamine (TMEDA), N , N ‘-dimethylpiperazine (DMP), and 1,4-diazabicyclo[2.2.2]octane (DABCO) each form a monoborane adduct which may be isolated and characterized. The monoborane adduct of TMEDA, 5 , and the monoborane adduct of DMP, 6 , are each unsymmetrical as evidenced by 1 H NMR.…”