Reaction scheme:
View attachment 1235
Reagents:
Indole, cas: 120-72-9
Dichloromethane, cas: 75-09-2
Tin tetrachloride, cas: 7646-78-8
1-naphthoyl chloride, cas: 879-18-5
Nitromethane, cas: 75-52-5
Ethyl acetate, cas: 141-78-6
Sodium hydroxide, cas: 1310-73-2
TBAB, cas: 1643-19-2
1-bromopentane, cas: 110-53-2
Water
Step 1. 3-(1-naphthoyl)indole.
View attachment 1236
1. To a stirring solution of indole (1000 g) in CH2Cl2(15 liters) was added SnCl4(2000 ml) in a single portion with an ice bath cooling.
2. After the ice bath was removed, the mixture was stirred at room temperature for 30 min, and then
1-naphthoyl chloride (1627 g) was added in small portions to the suspension, followed by nitromethane (10 liters).
3. The mixture was stirred for 2 h at room temperature.
4. After being quenched with ice and water (20 liters), organic material was extracted with ethyl acetate (15 liters) and the mixture was filtered to remove inorganic precipitates.
5. The organic phase was dried over Na2SO4 and concentrated at reduced pressure to give the 3-(1-naphthoyl) indole as a crystalline solid.
Step 2. 1-pentyl-3-(1-naphthoyl)indole.
View attachment 1237
1. Weigh 2000 g of the 3-(1-naphtoyl) indole, 1300 g sodium hydroxide, 800 g TBAB and add them into 10 L flask.
2. Pour 1500 g 1-bromopentane and 3000 ml of water into the flask.
3. Mix the reaction mixture, until two different layers are separated, and the entire hydroxide is dissolved.
4. When it dissolves, the flask will be heated.
5. As soon as two layers were divided and the entire hydroxide was dissolved, put the flask on the tile, and turn the heating to the maximum.
6. Install an overhead stirrer in the flask. It is necessary to mix well enough so that the layers are homogenized.
7. The overhead stirrer can work on constant stirring the entire reaction.
8. The heating at boiling continue until the contents of the flask appear to look as much as possible (several in the "milk" color), without a clear layer dedication (usually 15-30 min passes before).
9. Then remove the flask from heating and let it be to a clear separation into two layers.
10. We need the top layer. The product can crystallize directly in the flask, which makes it difficult to extract it. Therefore, we do everything quickly.
11. Remove the top layer neatly from the flasks into the glasses, or immediately into silicone forms.
12. Leave at room temperature by 24 hours until it hardens. We take silicone forms precisely for the ease of extracting the product after crystallization, it fully solidifies and takes the form, in which it was poured.
13. We take out and crush the crystallized product. Dry on paper and trays. With a warm room and ventilation, drying usually takes two days. Yield: 3000 g.
