- A novel diaminoborate ligand system derived from 1,8-diaminonaphthalene and 9-BBN: Preparation of titanium and zirconium complexes and crystal structure of the titanium complex
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1,8-Diaminonaphthalene reacts selectively with 1 equiv. of 9-BBN to form a bridging amine-aminoborane, and with 2 equiv. of 9-BBN to form a non-bridging bis(aminoborane); these aminoboranes give rise to a novel diaminoborate (4e,1-) ligand system by reactions with dimethylamides of titanium and zirconium.
- Bar-Haim, Galia,Shach, Romem,Kol, Moshe
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- Hydroboration Kinetics. 7. Kinetics and Mechanism of the Reduction of Aldehydes and Ketones with 9-Borabicyclononane Dimer
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The kinetics of the reduction of a number of aldehydes and ketones with 9-borabicyclononane dimer, (9-BBN)2, was studied at 25.0 deg C.The reduction of aldehydes and reactive ketones followed first-order kinetic behavior; with less reactive ketones, intermediate or three-halves-order kinetics was observed.Thus the mechanism is very similar to that of the hydroboration of alkenes and alkynes by (9-BBN)2, involving 9-BBN monomer as the intermediate.The relative rates of reduction of representative aldehydes and ketones were determined by the competitive method since the kinetic study could not reveal the effect of the structure upon the reactivity.A comparison with NaBH4 shows that (9-BBN)2 is less susceptible to steric effects, though the same trend is observed with both reagents.Increasing the steric hindrance on one side of the carbonyl function in ketones leads to a modest rate decrease while that on both sides leads to a considerable rate decrease.Electron-withdrawing substituents decrease and electron-releasing ones increase the rate of reduction of aldehydes and ketones.These facts strongly suggest that the boron atom of the reducing species, 9-BBN monomer, is coordinated with the carbonyl oxygen during the reduction process.
- Brown, Herbert C.,Wang, Kung K.,Chandrasekharan, J.
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- Interactions of C?F Bonds with Hydridoboranes: Reduction, Borylation and Friedel–Crafts Alkylation
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The stoichiometric reactions of the alkylfluorides 1-fluoroadamantane (Ad-F), fluorocyclohexane (Cy-F), 1-fluoropentane (Pent-F) and benzyl fluorides with secondary boranes pinacolborane (HBpin), catecholborane (HBcat), 9-borabicyclo(3.3.1)nonane (9-BBN)
- Bamford, Karlee L.,Chitnis, Saurabh S.,Qu, Zheng-wang,Stephan, Douglas W.
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supporting information
p. 16014 - 16018
(2018/10/15)
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- Pincer-ligated nickel hydridoborate complexes: The dormant species in catalytic reduction of carbon dioxide with boranes
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Nickel pincer complexes of the type [2,6-(R2PO) 2C6H3]NiH (R = tBu, 1a; R = iPr, 1b; R = cPe, 1c) react with BH3·THF to produce borohydride complexes [2,6-(R2/su
- Chakraborty, Sumit,Zhang, Jie,Patel, Yogi J.,Krause, Jeanette A.,Guan, Hairong
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- SALTS OF 2-FLUORO-N-METHYL-4-[7-(QUINOLIN-6-YL-METHYL)-IMIDAZO[1,2-b][1,2,4]TRIAZIN-2-YL]BENZAMIDE AND PROCESSES RELATED TO PREPARING THE SAME
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The present invention is directed to dihydrochloric acid and dibenzenesulfonic acid salts of the c-Met kinase inhibitor 2-fluoro-N-methyl-4-[7-(quinolin-6-ylmethyl)-imidazo[1,2-b][1,2,4]triazin-2-yl]benzamide, and pharmaceutical compositions thereof, useful in the treatment of cancer and other diseases related to the dysregulation of kinase pathways. The present invention further relates to processes and intermediates for preparing 2-fluoro-N-methyl-4-[7-(quinolin-6-ylmethyl)imidazo[1,2-b][1,2,4]triazin-2-yl]benzamide, and salts thereof.
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Page/Page column 22
(2009/12/05)
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- N-(2,4,6-trimethylborazinyl)-substituted boron, aluminum and titanium compounds
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The N-lithioborazine LiH2N3B3Me 3, 1, reacts with organoboron halides not only to the respective borazinyl organylboranes but also by Me/halogen exchange. (Me2N) 2B-H2N3B3Me3 was obtained from 1 and (Me2N)2BCl. A new ten-membered B 6N4 ring system, 5, results on treatment of Cl(Me 2N)B-B(NMe2)Cl with 1. The B-N-borazinyl borazines 6-8 can be prepared from 1 and B-monohalo borazines. The synthesis of 2,4,6-trimethylborazinyl-aluminum and -titanium compounds is achieved only with mononuclear monohalides of Al(III) and Ti(IV). The 2,4,6-trimethylborazinyl- bis(piperidino)alane 9 and the tris(2,6-diisopropylphenoxo)-2,4,6- trimethylborazinyltitanium 10 were characterized by X-ray structure analysis. The distortion of the borazine ring by B and N substitution is discussed. In case of the N-substituted borazines YH2N3B 3Me3 the B-N bonds of the YNB2 units are elongated, e. g. for Y = PBr2 or (RO)3Ti, while N lithiation leads to a shortening of these B-N bond. These changes of bond lengths are also reflected by changes in the B1-N2 and B3-N3 bond lengths which become shorter in the presence of electron-withdrawing groups, but longer in case of Li substitution. Also, the bond angles B1-N2-B2 and B2-N3-B3 are affected by an increase of up to 128°.
- Gemünd, Birgit,Günther, Berndt,Knizek, J?rg,N?th, Heinrich
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- Molecular addition compounds. 13. N,N-diisopropyl-n-isobutylamine-borane: The first highly reactive trialkylamine-borane reagent for hydroborations
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N,N-Diisopropyl-N-isobutylamine (1) forms a stable liquid borane adduct (4.7 M in BH3), when diborane is bubbled into the neat amine. The adduct thus formed is stable indefinitely at room temperature under an inert atmosphere. Hydroboration studies with this new, highly reactive amine-borane adduct, H3B:NPri2Bui (2) and representative olefins, such as 1-hexene, styrene, β-pinene, cyclopentene, norbornene, cyclohexene, 2-methyl-2-butene, α-pinene, and 2,3-dimethyl-2-butene, were carried out at room temperature (22 ± 3°C) in selected solvents, tetrahydrofuran, dioxane, tert-butyl methyl ether, n-pentane, and dichloromethane. The reactions are faster in dioxane and n-pentane, requiring ～2 h for the hydroboration of simple, unhindered olefins to the trialkylborane stage.
- Brown, Herbert C.
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p. 1310 - 1317
(2008/10/08)
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- Molecular addition compounds. 14. Convenient preparations of representative dialkylborane reagents using the new, highly reactive N- ethyl-N-isopropylaniline-borane reagent (BACH-EI(TM))
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Convenient procedures for the preparation of representative dialkylborane reagents, diisopinocampheylborane, [1S]-2-diisocaranylborane, 9-borabicyclo[3,3,1]nonane, dicyclohexylborane and disiamylborane, using the new, highly reactive N-ethyl-N-isopropylaniline-borane reagent (BACH-EI(TM)) in dioxane and tetrahydrofuran are described.
- Brown, Herbert C.,Kanth, Josyula V. B.,Zaidlewicz, Marek
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p. 5991 - 6000
(2007/10/03)
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- Contributions to the Chemistry of Boron, 215. - Synthesis and Reactions of Monomeric Tetraorganyl-phosphanylboranes
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The reaction of diorganyl-chloroboranes with lithium diorganyl- or lithium bis(trimethylsilyl)phosphides leads to the monomeric phosphanylboranes tBu2BPtBu2 (1), tBu2BP(SiMe3)2 (2), 9-BBNPtBu2 (3), 9-BBNP(SiMe3)2 (4), and Cy2BPtBu2 (5).These species were studied by NMR-spectroscopic methods.For further characterization reactions of the compounds 1, 3, and 5 have been investigated.Heating of 1 and 5 results in the formation of the dimeric phosphanylboranes tBu(H)BPtBu2 (8) and Cy(H)BPtBu2 (9) by dehydroboration.Dimers 8 and 9 are present as cis- and trans-isomers asconfirmed by X-ray structure analyses.The trans isomer of 9 shows a planar (BP)2 four-membered ring, whereas the ring of the cis-isomer of 8 is slightly folded.Furthermore, the reaction of 3 with 9H-9-BBN yields (μ-H)(μ-tBu2P)2 (14), whose bridged structure is proven by a crystal structure analysis.Oxidation of the phosphorus atom in 3 with sulfur leads to the S-boryl thiophosphinate tBu2(S)PS-9-BBN (16). Key Words: Phosphanylboranes, tetraorganyl/1,3,2,4-Diphosphadiboracyclobutane/Diboranes, μ-phosphanyl-/Thiophosphinate, S-boryl.
- Noeth, Heinrich,Staude, Siegfried,Thomann, Martina,Paine, Robert T.
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p. 611 - 618
(2007/10/02)
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- ORGANOBORANES. XXV. HYDRIDATION OF DIALKYLHALOBORANES. NEW PRACTICAL SYNTHESES OF DIALKYLBORANES UNDER MILD CONDITIONS
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Practical methods for the synthesis of dialkylboranes (R2BH) via the hydridation of dialkylhaloboranes (R2BX) have been developed.Convenient methods available for the preparation of R2BX via the hydroboration of alkenes with monohaloborane complexes (H2BX*SMe2) make this approach valuable for the preparation of various dialkylboranes, R2BH, many of which are not available by direct hydroboration of alkenes with borane itself.The suitability of various hydriding agents, such as borane derivatives, complex metal hydrides, and alkoxy metal hydrides, for the hydridationof R2BX was examined, utilizing B-halo-9-borabicyclononane as a representative dialkylhaloborane.In this case, the unusual stability of the resulting dialkylborane, 9-BBN, permits direct estimation of the reaction products by 11B NMR spectroscopy.The generality of the procedure has been demonstrated.
- Brown, Herbert C.,Kulkarni, Surendra U.
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p. 299 - 308
(2007/10/02)
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