问题：氯甲酸苄酯的性质和一个氨基保护反应
类型：求助 (悬赏分:3分)
提问：barbara730
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版块：药物化学(jaywoo,合成小象,)
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回复：14
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时间：2006-04-11 19:18:25 编辑加入/取消收藏订制/取消短消息举报该贴

我要做一个用氯甲酸苄酯保护氨基的反应，查了氯甲酸苄酯的性质，遇水和醇分解，而一些文献中有在碳酸钠水溶液中反应的，这样不会分解吗？
另外原料2-氨基-4-磺酸基苯甲酸，试了几种有机溶剂溶解性都很差，在水中溶解，如果反应在水中进行我担心氯甲酸苄酯水解。请高手指点该反应如何进行，要注意哪些问题？谢谢！

回复人：edwin,★★ (宝剑锋从磨砺出,梅花香自苦寒来) 时间：2006-04-11 20:11:21 编辑	1楼
我觉得你用碳酸钠水溶液应该可以的,因为氯甲酸苄酯是很常用的保护氨基酸的基团.你先把2-氨基-4-磺酸基苯甲酸和碳酸钠配制成水溶液,控制好pH(一般在8-9),然后滴加氯甲酸苄酯,反应过程中控制好pH值,用TLC监测

回复人：ykmsx,▲ () 时间：2006-04-12 15:26:57 编辑	2楼
碱性条件分解很慢,一般可以达到目的

回复人：lactams,▲ () 时间：2006-04-12 15:36:23 编辑	3楼
碳酸钠水溶液中反应,加点丙酮之类的水溶性有机溶剂

回复人：chimeralu,★ (拼命在一线工作，大量地阅读文献.) 时间：2006-04-13 15:41:54 编辑	4楼
Na2CO3碱性没问题的，NaOH也可以。控制PH，水解不快的，还可以双滴加。丙酮、二噁烷加入对反应可能有好处，可以试试。

回复人：ballon,▲▲▲ (应用化学（商品检验与城市环境检测）) 时间：2006-04-13 19:30:16 编辑

5楼

【中文名称】氯甲酸苄酯；苄酯基氯；苯甲氧甲酰氯；氯碳酸苯甲基酯

【英文名称】benzyl chloroformate;chloroformic acid benzyl ester;CBZ-Cl;Z-Cl

【结构或分子式】

【相对分子量或原子量】170.60

【密度】1.195

【沸点（℃）】103（2.666E3Pa）；85～87（0.933E3Pa）

【闪点（℃）】92

【折射率】1.5160

【毒性LD50(mg/kg)】

小鼠经口3300

【性状】

无色至浅黄色油状液体，有刺激性和催泪性。

【溶解情况】

溶于乙醚和丙酮，在水和乙醇中分解。

【用途】

用于有机合成，特别是作为缩氨酸合成时氨基保护剂，甜味剂天冬甜母合成时的氨基保护剂；合成氨苄青霉素时作为苯基甘氨酸（原料）的氨基保护剂。

【制备或来源】

以苄醇和光气为原料，在低温光照下进行反应，生成粗品，减压蒸馏除去未反应的光气，副产的氯化氢及溶剂甲苯后，再收取103℃（2.666E3Pa）的馏分而得。

【其他】

加热易产生二氧化碳，并生成氯苄。需要冷藏保存。

回复人：barbara730,▲ () 时间：2006-04-18 20:52:27 编辑	6楼
谢谢各位这个反应的产物在酸性或碱性水溶液中会不会分解？以前看过一篇文献，类似结构的化合物有水解的问题

回复人：upstart,★ (药物设计及合成,感兴趣精细化工) 时间：2006-04-19 11:53:55 编辑	7楼
~{L<KaDFK.H\R:VP74S&~},~{<SR;P)~}dioxane

回复人：csali3911,▲▲ (没有描述就是好描述!) 时间：2006-11-14 22:47:34 编辑

8楼

Benzyl chloroformate
Benzyl chlorocarbonate
Carbobenzoxy chloride

Formula C8H7ClO2
Structure
Description A colorless liquid with an acrid odor.
Uses In peptide synthesis to block the amino group.

Registry Numbers and Inventories.
CAS 501-53-1
EC (EINECS/ELINCS) 207-925-0
EC Index Number 607-064-00-4
EC Class Corrosive; Dangerous for the Environment
EC Risk Phrase R 34 50/53
EC Safety Phrase S 26 45 60 61
RTECS LQ5860000
RTECS class Other
UN (DOT) 1739
Merck 13,1810
Beilstein/Gmelin 509751
Beilstein Reference 4-06-00-02278
US TSCA Listed
Austrailia AICS Listed
Japan ENCS (MITI) Listed
Korea ECL Listed

Properties.
Formula C8H7ClO2
Formula mass 170.60
Melting point, °C -18
Boiling point, °C 103
Vapor pressure, mmHg 0.094 (25 C)
Density 1.22 g/cm3 (20 C)
Solubility in water Insoluble.
Viscosity 2.57 MPa-s@ 20C
Surface tension 25 g/s2
Refractive index 1.5190 (20 C)
Partition coefficient, pKow 2.69
Heat of vaporization 46.1 kJ/mol
Heat of combustion -5117 kJ/mol

Hazards and Protection.
Storage Keep away from heat, sparks, and flame. Keep away from sources of ignition. Store in a cool, dry place. Keep refrigerated.
Handling Wash thoroughly after handling. Wash hands before eating. Remove contaminated clothing and wash before reuse. Use only in a well ventilated area. Do not get in eyes, on skin, or on clothing. Avoid contact with heat, sparks and flame. Do not ingest or inhale.
Protection Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container. Clean up spills immediately, using the appropriate protective equipment. Scoop up with a nonsparking tool, then place into a suitable container for disposal.
Stability Substance is shock sensitive and thermally unstable. Decomposes when heated.
Incompatibilities Acids. Can react with rust from corroded equipment. Iron salts catalyze explosive decomposition of ester. Reacts with water or steam.
Decomposition Hydrogen chloride, chlorine, phosgene, carbon monoxide, carbon dioxide.

Fire.
Flash Point,°C 91
Autoignition, °C 590
Fire fighting Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Reacts violently with water. Extinguishing media: Do NOT use water directly on fire. Use foam, dry chemical, or carbon dioxide.
Fire potential Combustible
Hazards Substance will react with water (some violently), releasing corrosiveand/or toxic gases.
Combustion products Toxic phosgene, hydrogen chloride, and benzyl chloride vapors may form.
NFPA Health 3
Flammability 1
Reactivity 0

Health.
Poison_Class 3 (Strong toxins)
Exposure effects Agitation and syncope, both attributed to panic, have been reported.
Ingestion May cause severe gastrointestinal tract irritation with nausea, vomiting and possible burns.
Inhalation May cause severe irritation of the respiratory tract with sore throat, coughing, shortness of breath and delayed lung edema. Causes chemical burns to the respiratory tract. Inhalation may be fatal as a result of spasm, inflammation, edema of the larynx and bronchi, chemical pneumonitis and pulmonary edema.
Skin May cause severe irritation and possible burns.
Eyes Contact with eyes may cause severe irritation, and possible eye burns. Lachrymator.

First aid
Ingestion Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
Inhalation Get medical aid immediately. Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen.
Skin Get medical aid immediately. Immediately flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes.
Eyes Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.

Transport.
UN number 1739
Response guide 137
Hazard class 8
Packing Group I
USCG CHRIS Code BCF
HS Code 2915 90 20
Std. Transport # 4933010

回复人：jackzwl,▲ () 时间：2009-05-11 10:48:28 编辑	9楼
氯甲酸苄酯保护氨基的反应温度应该控制在多少？反应过程中需要加DIPEA吗？谢谢！急急急！我做的是氯甲酸苄酯和B-CH2-CH2-NH-CH2-CH2-B的反应，其中B代表苯环！急急急！

回复人：chemwu70,★ (共同进步) 时间：2009-05-11 19:13:04 编辑	10楼

回复人：qingyi,▲ (努力学习) 时间：2009-05-23 14:10:50 编辑	11楼
物化性质(Physical Properties) 　　1、含量：≥98%；2、性状：无色至黄色油状液体，有强刺激味；3、沸点：103℃；4、比重：1.195-1.22；5、用途：用于有机合成的中间体　　用途(Useage) 　　在抗生素合成中作氨基保护剂，也用于农药中间体

回复人：alistjun,▲ ( 做人踏实，喜欢学习自己喜欢的东西！) 时间：2009-09-10 20:30:08 编辑	12楼
用30%碳酸钾溶液，加入溶剂和反应物降温在0~10度，缓慢滴加到反应体系中，这个反应在1小时基本就OK了。氯甲酸苄酯保只要不在强碱条件下是很稳定的，这个反应我在做，反应效果不错的。

回复人：分析哎呀,▲ (需要学习的很多~尤其是有机的哥哥姐姐们~拜托咯~) 时间：2010-01-19 14:30:51 编辑	13楼
我是分析专业的~但是这次也涉及到了合成，就是用cbz氨基保护的反应~！但是我是微量合成，请问这个方法也适用么?还有就是cbz过量的多些也可以么~请各位哥哥姐姐帮助我~

回复人：gyysyw,▲ () 时间：2012-06-15 13:59:54 编辑	14楼
我最近也在做，怎么就不行呢

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