22093-04-5

Upstream product

• 131765-96-3 dicyclohexylamine borane complex 
• 14040-11-0 tungsten hexacarbonyl 
• 199620-14-9 chromium⁽⁰⁾ hexacarbonyl 
• 1722-26-5 triethylamine-borane 
• 101-83-7 N-cyclohexyl-cyclohexanamine 

Downstream Products

• 1073349-30-0 [Rh(H)2(η2-H2BNCy2)(P(i-Bu)3)2][B(3,5-C6H3(CF3)2)4] 
• 22093-03-4 HB{N(c-C₆H₁₁)2}2 
• 22571-48-8 (diethyl)(dicyclohexylamino)borane 
• 22516-34-3 C₂H₅BHN(c-C₆H₁₁)2 

Relevant academic research and scientific papers

Magnesium promoted autocatalytic dehydrogenation of amine borane complexes: A reliable, non-cryogenic, scalable access to boronic acids

Owing to the unusual reactivity of dialkylamine-borane complexes, a methodology was developed to simply access boronic acids. The intrinsic instability of magnesium aminoborohydride was tweaked into a tandem dehydrogenation borylation sequence. Proceeding via an autocatalytic cycle, amineborane dehydrogenation was induced by a variety of Grignard reagents. Overall, addition of the organomagnesium species onto specially designed dialkylamine-borane complexes led to a variety of boronic acids in high yields. In addition, the reaction can be performed under Barbier conditions, on a large scale.

METHODS OF PREPARATION OF AMINOBORANES AND APPLICATIONS FOR BORYLATION AND SUZUKI COUPLING

The present invention relates to a process for the preparation of aminoboranes (RR′N—BH2), and aminoborane-amine complexes (RR′N—BH2:NRR′R″), wherein R, and R′ of the aminoborane can be the same or different alkyl groups, and R, R′, and R″ of the amine complex can be the same or different alkyl groups or hydrogen. The dialkylaminoboranes have been utilized for the preparation of aryl and alkenylboronate esters via dehaloborylation of the corresponding aryl or alkenyl halides, followed by treatment with alcohols or diols. The process and the products thereof are within the scope of this disclosure.

Stoichiometric reactions and catalytic dehydrogenations of amine-boranes with calcium aryloxide

Catalysis with the main-group metal calcium conventionally relies on σ-bond metathesis to initiate the reactions. Here, we report a calcium aryloxide based on the tridentate β-diketiminato ligand, which shows transition-metal-like reactivity with dialkyla

Borinic Acids via Direct Arylation of Amine-Borane Complexes: An Air- and Water-Stable Boron Source

A synthesis of borinic acids and borinates was optimized using amine-borane complexes as a water and air insensitive borylating agent. The reaction operates under convenient conditions using a non-cryogenic temperature and with no flash chromatography, and it gives no boron impurities. The reaction proceeds through a tandem dehydrogenation-double addition mechanism.

Dehydrocoupling reactions of secondary and primary amine-borane adducts catalyzed by half-sandwich carbonyl complexes, [CpMn(CO)3], [(η6-C6H6)Cr(CO)3], and [CpV(CO)4]

Dehydrocoupling reactions of amineborane adducts catalyzed by half-sandwich carbonyl complexes are described. Secondary amine-borane adducts released H2 with catalytic action of [CpMn(CO)3] (Cp: η5-C5H5/su

Dehydrogenation of saturated CC and BN bonds at cationic N-heterocyclic carbene stabilized M(III) centers (M = Rh, Ir)

Chloride abstraction from the group 9 metal bis(N-heterocyclic carbene) complexes M(NHC)2(H)2Cl [M = Rh, Ir; NHC = IPr = N,N′-bis(2,6-diisopropylphenyl)imidazol-2-ylidene or IMes = N,N′-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene] leads to the formation of highly reactive cationic species capable of the dehydrogenation of saturated CC and BN linkages. Thus, the reaction of Ir(IPr)2(H)2Cl (1) with Na[BArf4] in fluorobenzene generates [Ir(IPr)2(H)2]+[BArf 4]- (4) in which the iridium center is stabilized by a pair of agostic interactions utilizing the methyl groups of the isopropyl substituents. After a prolonged reaction period C-H activation occurs, ultimately leading to the dehydrogenation of one of the carbene iPr substituents and the formation of [Ir(IPr)(IPr′′)(H) 2]+[BArf4]- (5), featuring the mixed NHC/alkene donor IPr′′ ligand. By contrast, the related IMes complexes M(IMes)2(H)2Cl (M = Rh, Ir), which feature carbene substituents lacking β-hydrogens, react with Na[BAr f4] in fluorobenzene to give rare examples of NaCl inclusion compounds, viz., [M(IMes)2(H)2Cl(Na)] +[BArf4]- (M = Rh, 6; M = Ir, 7). Intercalation of the sodium cation between the mesityl aromatic rings of the two NHC donors has been demonstrated by crystallographic studies of 7. Synthetically, 6 and 7 represent convenient yet highly reactive sources of the putative 14-electron [M(NHC)2(H)2]+ cations, readily eliminating NaCl in the presence of potential donors. Thus 7 can be employed in the synthesis of the dinitrogen complexes [Ir(IMes) 2(N2)2]+[BArf 4]- (8a) and [Ir(IMes)2(N2)THF] +[BArf4]- (8b) (albeit with additional loss of H2) by stirring in toluene under a dinitrogen atmosphere and recrystallization from the appropriate solvent system. The interactions of 6 and 7 with primary, secondary, and tertiary amineboranes have also been investigated. Although reaction with the latter class of reagent simply leads to coordination of the amineborane at the metal center via two M-H-B bridges {and formation, for example, of the 18-electron species [M(IMes)2(H)2(μ-H)2B(H)NMe3] +[BArf4]- (M = Rh, 9; M = Ir, 10)}, the corresponding reactions with systems containing N-H bonds proceed via dehydrogenation of the BN moiety to give complexes containing unsaturated aminoborane ligands. Thus, for example, 6 catalyzes the dehydrogenation of R2NHBH3 (R = iPr, Cy) in fluorobenzene solution (100% conversion over 6 h at 2 mol % loading) to give R2NBH 2; the organometallic complex isolated at the end of the catalytic run in each case is shown to be [Rh(IMes)2(H)2(μ-H) 2BNR2]+[BArf4] - (R = iPr, 11; R = Cy, 12). In contrast to isoelectronic alkene donors, the aminoborane ligand in these complexes (and in the corresponding iridium compounds 13 and 14) can be shown by crystallographic methods to bind in end-on fashion via a bis(s-borane) motif. Similar dehydrogenation chemistry is applicable to the primary amineborane tBuNH2BH3, although in this case the rate of rhodium-catalyzed dehydrogenation is markedly slower. This enables the amineborane complex [Rh(IMes)2(H)2(μ-H) 2B(H)NH2tBu]+[BArf 4]- (15) to be isolated at short reaction times (ca. 6 h) and the corresponding (dehydrogenated) aminoborane system [Rh(IMes) 2(H)2(μ-H)2BNHtBu] +[BArf4]- (16) to be isolated after an extended period (ca. 48 h). As far as further reactivity is concerned, aminoborane systems such as 14 show themselves to be amenable to further dehydrogenation chemistry in the presence of tert-butylethylene leading ultimately to the dehydrogenation of the boron-containing ligand and to the formation of a directly Ir-B bonded system described by limiting boryl (Ir-B) and borylene (Ir=B) forms.

Dehydrocoupling reactions of borane-secondary and -primary amine adducts catalyzed by group-6 carbonyl complexes: Formation of aminoboranes and borazines

Photoirradiation of a solution of BH3·NHR2 (1a: R = Me, 1b: R = 1/2C4H8, 1c: R = 1/2C 5H10, 1f: R = Et) containing a catalytic amount of a group-6 metal carbonyl complex, [M(CO)6] (M = Cr, Mo, W), led to dehydrogenative B-N covalent bond formation to produce aminoborane dimers, [BH2NR2]2 (2a-c, f), in high yield. During these reactions a borane σ complex, [M(CO)5(η1- BH3·NHR2)] (3), was detected by NMR spectroscopy. Similar catalytic dehydrogenation of bulkier amineboranes, BH 3·NHiPr2 (1d) and BH3· NHCy2 (1e, Cy = cyclo-C6H11), afforded monomeric products BH2=NR2 (4d, e). The reaction mechanism of the dehydrocoupling was investigated by DFT calculations. On the basis of the computational study, we propose that the catalytic dehydrogenation reactions proceed via an intramolecular pathway and that the active catalyst is [Cr(CO)4]. The reaction follows a stepwise mechanism involving NH and BH activation. Dehydrocoupling of borane-primary amine adducts BH 3·NH2R (1g: R = Me, 1h: R = Et, 1i: R = tBu) gave borazine derivatives [BHNR]3 (5g-i).

Lithium aminoborohydrides 16. Synthesis and reactions of monomeric and dimeric aminoboranes

(Chemical Equation Presented) Aminoboranes are synthesized in situ from the reaction of the corresponding lithium aminoborohydrides (LABs) with methyl iodide, trimethylsilylchloride (TMS-Cl), or benzyl chloride under ambient conditions. In hexanes, the reaction using methyl iodide produces aminoborane and methane, whereas in tetrahydrofuran (THF) this reaction produces amine-boranes (R1R2HN:BH3) as the major product. The reaction of iPr-LAB with TMS-Cl or benzyl chloride yields exclusively diisopropylaminoborane [BH2-N(iPr)2] in THF as well as in hexanes at 25°C. Diisopropylaminoborane and dicyclohexylaminoborane exist as monomers due to the steric requirement of the alkyl group. All other aminoboranes studied are not sterically hindered enough to be monomers in solution, but instead exist as a mixture of monomers and dimers. The dimers are four-membered rings formed through boron-nitrogen coordination. In general aminoboranes are not hydroborating reagents. However, monomelic aminoboranes, such as BH2-N(iPr)2, can reduce nitriles in the presence of catalytic amounts of LiBH4. This BH 2-N(iPr)2/LiBH4 reducing system also reduces ketones, aldehydes, and esters. Diisopropylaminoborane, synthesized from iPr-LAB, can be converted into boronic acids by a palladium-catalyzed reaction with aryl bromides. Aminoboranes derived from heterocyclic amines, such as pyrrole, pyrazole, and imidazole, can be prepared by the direct reaction of borane/tetrahydrofuran (BH3:THF) with these heterocyclic amines. It has been reported that pyrazole-derived aminoborane forms a six-membered dimer through boron-nitrogen coordination, where as, pyrrolylborane forms a dimer through boron-hydrogen coordination. Pyrrolylborane monohydroborates both alkenes and alkynes at ambient temperatures. Hydroboration of styrene with pyrrolylborane followed by hydrolysis gives the corresponding boronic acid, 2-phenylethylboronic acid, in 40% yield. Similarly phenylacetylene is mono-hydroborated by pyrrolylborane, to give E-2-phenylethenylboronic acid in 50% yield.

(Aryl)(amino) borane compounds, method for preparing same

The invention concerns (aryl)(amino)borane compounds and a method for preparing same. Said compounds are of formula A-BH-NR1R2, wherein: R1 and R2 are selected among linear, branched or cyclic alkyl radicals, an

Monomeric (dialkylamino)boranes: A new and efficient boron source in palladium catalyzed C-B bond formation with aryl halides

Thermal decomposition of hindered amine-borane adducts leads in high yields to monomeric (dialkylamino)boranes R1R2N-BH 2 (R1 and R2 = alkyl) that are new and efficient boron-sources in the Pd0/