• 대한화학회지
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• 제22권4호
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• pp.259-267
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• 1978

수소화붕소리튬, 보란 그리고 보란-염화리튬(1:0.1)의 카르보닐화합물 환원에 있어서의 선택성을 5쌍의 대표적인 카르보닐화합물 쌍(벤즈알데히드-아세토페논, 벤즈알데히드-2-헵탄온, 2-헵탄온-벤조페논, 아세토페논-벤조페논, 2-헵탄온-아세토페논)에 대해서 이들 수소화물의 제한된 양을 반응시켜 알아보았다. 이들 수소화물중 보란-염화리튬(1:0.1)이 제일 선택성이 좋았고, 수소화붕소 리튬과 보란도 2-헵탄온-아세토페논 쌍을 제외하고는 좋은 선택성을 보였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.252.1-252.1
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• 2013

Hexagonal boron nitride (h-BN) is a two dimensional material which has high band-gap, flatness and inert properties. This properties are used various applications such as dielectric for electronic device, protective coating and ultra violet emitter so on. 1) In this report, we were growing h-BN sheet directly on sapphire 2"wafer. Ammonia borane (H3BNH3) and nickel were deposited on sapphire wafer by evaporate method. We used nickel film as a sub catalyst to make h-BN sheet growth. 2) During annealing process, ammonia borane moved to sapphire surface through the nickel grain boundary. 3) Synthesized h-BN sheet was confirmed by raman spectroscopy (FWHM: ~30cm-1) and layered structure was defined by cross TEM (~10 layer). Also we controlled number of layer by using of different nickel and ammonia borane thickness. This nickel film supported h-BN growth method may propose fully and directly growing on sapphire. And using deposited ammonia borane and nickel films is scalable and controllable the thickness for h-BN layer number controlling.

• 한국수소및신에너지학회논문집
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• 제25권5호
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• pp.475-481
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• 2014

Ammonia borane ($NH_3BH_3$), as a source material for energy generation and hydrogen storage, has attracted growing interest due to its high hydrogen content. We have investigated the synthesis of ammonia borane from sodium borohydride ($NaBH_4$) and ammonium chloride ($NH_4Cl$) utilizing a low-temperature process. From our results, we obtained a maximum synthetic yield of 98.2% of ammonia borane complex. The diammoniate diborane (DADB) was detected in about 5~10mol% with in the solid ammonia borane by solid-state $^{11}B$-NMR analysis. The synthesized solid ammonia borane products were studied to characterize hydrogen release upon thermal dehydrogenation.

• Advances in Energy Research
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• 제4권2호
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• pp.177-187
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• 2016

Ammonia borane $NH_3BH_3$ solubilized in organic solvent is a potential liquid-state chemical hydrogen storage material. In this study, metal acetylacetonates like $Fe(O_2C_5H_7)_3$, $Co(O_2C_5H_7)_2$, $Ni(O_2C_5H_7)_2$, $Pd(O_2C_5H_7)_2$, $Pt(O_2C_5H_7)_2$ and $Ru(O_2C_5H_7)_3$ are considered for assisting dehydrocoupling of ammonia borane in diglyme (0.135 M) at $50^{\circ}C$. The molar ratio between ammonia borane and metal acetylacetonate is fixed at 100. A protocol for the separation of the soluble and insoluble fractions present in the slurry is proposed; it consists in using acetonitrile to make the precipitation of metal-based compounds easier and to solubilize boron-based intermediates/products. The nature of the metal does not affect the dehydrocoupling mechanisms, the $^{11}B\{^1H\}$ NMR spectra showing the formation of the same reaction intermediates. The aforementioned metal acetylacetonates do mainly have effect on the kinetics of dehydrocoupling. Dehydrocoupling takes place heterogeneously and dehydrogenation of ammonia borane in these conditions leads to the formation of polyborazylene via intermediates like e.g., B-(cyclodiborazanyl) amine-borane and borazine. Our main results are reported and discussed herein.

• Bulletin of the Korean Chemical Society
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• 제33권4호
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• pp.1275-1278
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• 2012

Tris(pentafluorophenyl)borane, $B(C_6F_5)_3$, was found to be an efficient catalyst for synthesis of N-Cbzhomoallylic amines using Sakurai allylation of N-benzyloxycarbonyl-amino p-tolylsulfones with allyltrimethylsilane.

• Bulletin of the Korean Chemical Society
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• 제22권10호
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• pp.1089-1092
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• 2001

• Bulletin of the Korean Chemical Society
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• 제22권3호
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• pp.325-326
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• 2001

• 대한화학회지
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• 제44권4호
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• pp.387-390
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• 2000

• 대한화학회지
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• 제43권3호
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• pp.366-369
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• 1999

• Bulletin of the Korean Chemical Society
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• 제7권4호
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• pp.296-298
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• 1986

Carboxylic acid anhydrides are rapidly reduced with borane-lithium chloride (1:0.1) system to give corresponding alcohols (diols in the case of cyclic anhydride) quantitatively in tetrahydrofuran at room temperature. This reagent tolerates aromatic acid ester, nitro, and halide functional groups, however competitively reduces aliphatic ester and nitrile groups.