化合物简介
Sodium triacetoxyborohydride, also known as sodium triacetoxyhydroborate, commonly abbreviated STAB, is a chemical compound with the formula Na(CH3COO)3BH. Like other borohydrides, it is used as a reducing agent in organic synthesis. This colourless salt is prepared by protonolysis of sodium borohydride with acetic acid:
NaBH4 + 3 HO2CCH3 → NaBH(O2CCH3)3 + 3 H2
Owing to the steric and electronic effects of the acetoxy groups, sodium triacetoxyborohydride is a milder reducing agent than sodium borohydride or even sodium cyanoborohydride. Furthermore, NaBH(OAc)3 avoids the toxic side-products generated by sodium cyanoborohydride. Sodium triacetoxyborohydride is especially suitable for reductive aminations of aldehydes and ketones.
However, unlike sodium cyanoborohydride, the triacetoxyborohydride is water-sensitive, and water cannot be used as a solvent with this reagent, nor is it compatible with methanol. It reacts only slowly with ethanol and isopropanol and can be used with these.
NaBH(OAc)3 may also be used for reductive alkylation of secondary amines with aldehyde-bisulfite adducts.
NaBH4 + 3 HO2CCH3 → NaBH(O2CCH3)3 + 3 H2
Owing to the steric and electronic effects of the acetoxy groups, sodium triacetoxyborohydride is a milder reducing agent than sodium borohydride or even sodium cyanoborohydride. Furthermore, NaBH(OAc)3 avoids the toxic side-products generated by sodium cyanoborohydride. Sodium triacetoxyborohydride is especially suitable for reductive aminations of aldehydes and ketones.
However, unlike sodium cyanoborohydride, the triacetoxyborohydride is water-sensitive, and water cannot be used as a solvent with this reagent, nor is it compatible with methanol. It reacts only slowly with ethanol and isopropanol and can be used with these.
NaBH(OAc)3 may also be used for reductive alkylation of secondary amines with aldehyde-bisulfite adducts.
基本信息
- 中文名称：
- 三乙酰氧基硼氢化钠
- 中文别名：
- 三乙酰基硼氢化钠
- 英文名称：
- Sodium Triacetoxyborohydride
- 英文别名：
- sodium,triacetyloxyboron(1-)
- CAS号：
- 56553-60-7
- 分子式：
- C6H9BNaO6
- 分子量：
- 210.93300
- 精确质量：
- 211.03900
- PSA：
- 78.90000
物化性质
- 外观与性状：
- 白色结晶粉末
- 熔点：
- 116-120 °C (dec.)(lit.)
- 水溶解性：
- reacts
- 稳定性：
- Reacts violently with water.
- 储存条件：
- Flammables + water-Freezer (-20ºC)e area
安全信息
- 包装等级：III
- 危险类别：4.3
- 海关编码：2942000000
- 危险品运输编码：UN 1409 4.3/PG 2
- WGK Germany：3
- 危险类别码：R14/15; R34
- 安全说明：S43-S7/8-S45-S36/37/39-S26
- 危险品标志：F; C
生产方法及用途
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生产方法
1. 将4当量氢化硼钠悬浮于苯中,加入3.25当量冰乙酸,使混合物在氮气保护下回流15分钟。当最初产生的大量气体(约3摩尔氢气)平息后,得清彻的三乙酰氧基氢化硼钠苯溶液。
用途
三乙酰氧基硼氢化钠是近年来开发的一种新的用于还原胺化的催化剂，因其具有极好的普适性和选择性，反应条件温和，催化还原性能好，且易于分离纯化，对环境没有污染，成为还原胺化反应首选的催化剂。
