Vanillin


香草醛

Sodium borohydride


硼氫化鈉

1M Sodium hydroxide, 3M hydrochloric acid and
95% Ethanol


1M 氫氧化鈉， 3M 氫氯酸和95%乙醇

Weigh accurately 1 g of vanillin solid in a
25 cm³ conical flask.


將1 g的香草醛準確稱重加入25 cm³ 的錐形瓶。

Add 2 cm³ of 95 % ethanol and a magnetic
stir bar into the flask. Stir the mixture with
an electric stir plate at room temperature.  


在錐形瓶加入2 cm³ 的95% 乙醇和一枚磁攪拌棒 。
將瓶置於電動攪拌板上，在室溫下攪拌混合物。

Cool the mixture in an ice-water bath.


用冰水浴將混合物冷卻。

Prepare NaBH₄ solution by dissolving 0.25g
of NaBH₄ solid with 1M NaOH. Slowly add the
solution dropwise to the mixture with dropper.


將0.25g的NaBH₄固體溶於1M的NaOH製備出
NaBH₄溶液。用滴管慢慢將NaBH₄溶液逐滴加
至香草醛溶液。

Remove the flask from the ice-water bath and
allow the reaction mixture to be stirred at room
temperature for 10 minutes.


自冰水浴中取出錐形瓶，在室溫下把反應混合物
攪拌10分鐘。

Cool the reaction mixture again with an
ice-water bath.


再將反應混合物置於冰水浴中。

Add 3M HCl(aq) dropwise to the reaction
mixture.


把3M HCl(aq) 逐滴加進反應混合物。

Continue the addition until no more gas evolves
from the mixture or until the reaction mixture is
acidic. The acidity can be checked by pH paper.


加入HCl(aq) 直至再沒有任何氣體自混合物釋出或
直至反應混合物呈酸性。可以使用pH試紙測試其
酸性。

Cool the mixture with continuous stirring to allow
the product to precipitate from the reaction mixture.


在持續攪拌下將混合物冷卻，讓產物從反應混合物
中沉澱出來。

Assemble the apparatus for suction filtration.


組裝吸濾法的裝置。

Transfer the product mixture with small amount
of ice-cold water to the Buchner funnel to collect
the solid product.Wash the product twice with
small amount of ice-cold water. Leave the product
on the Buchner funnel to dry.


用少量冰水將產物混合物轉移至布赫勒爾漏斗以
收集固體產物。用冰水清洗產物兩次。讓產物留
在布赫勒爾漏斗弄乾。

When the product is dried, collect the product
and weigh it.


當弄乾產物後，收集產物並稱重。

Prepare the TLC sample by dissolving a small
amount of the product in 1 cm³ of propanone
in a small test tube. The authentic solutions of
vanillin and vanillyl alcohol were prepared.


在小試管中用1 cm³ 的丙酮溶解少量產物，以
製備TLC樣本。真確香草醛溶液和香草醇溶液
亦以此方法製備出來。

 Capillary tube


毛細管

Prepare the TLC chamber by adding an appropriate
amount of TLC solvent (hexane / ethyl ethanoate
3:2) into the chamber to about 3-4 mm deep.


在TLC室加入適當分量的TLC溶劑 (己烷 / 乙酸乙酯
 3:2) 直至溶劑深度約為3-4 mm。

TLC plate


TLC板

Spot the sample solution and authentic solutions
on a TLC plate by using a capillary tube.


用毛細管將樣本溶液和真確溶液點在TLC板上。

Place the TLC plate vertically into the chamber
carefully and close the lid. When the development
is finished, take the TLC plate out of the chamber.


小心地將TLC板垂直放置於TLC室並蓋上TLC室。
當展開完成後，取出TLC板。

Prepare an iodine chamber by placing a few
crystals of iodine into a clean TLC chamber.


在一個潔淨的TLC室中加入數塊碘結晶以配備碘室。

Put the developed TLC plate into the iodine
chamber and close the lid.  Wait till visible
spots are formed on the plate.


將已展開的TLC板放置於碘室中，然後蓋好
碘室。等待至板上有可見斑點出現。

TLC result after development in iodine chamber


在碘室展開後的TLC結果。