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ChemicalBook CAS DataBase List 3-Butylidenephthalide
551-08-6

3-Butylidenephthalide synthesis

10synthesis methods
-

Yield:551-08-6 76.1%

Reaction Conditions:

with sodium valerate at 170 - 190; for 4 h;

Steps:

1; 4 Example 4 Preparation and distillation of butenephthalide (DBT-1)

441.41 g of pentanoic acid anhydride,Phthalic anhydride 386.59g,Sodium valerate 117.81g, added to the 5L reaction flask,Stir well and mix well,Heated to about 170 for 1h;Followed by additional sodium valerate 118.00g, and then warmed to about 190 , the reaction was continued warm 3h; the reaction completed, the system was cooled to about 100 , dropping 1L deionized water, heating was continued to return,Continue to reflow 1h, cooling, down to room temperature; control system temperature at about 25 ,The mixture was adjusted to pH 9 with concentrated aqueous ammonia, extracted three times with 2.5 L of dichloromethane, washed twice with 1 L of dilute ammonia (1%), twice with 1 L of deionized water and dried with 100 g of anhydrous calcium chloride, filtered with suction to remove the desiccant , Concentrated dichloromethane recovery, was dark red oily liquid, 20cm long thorn-type distillation column vacuum distillation,Collected 140 ~ 145 / 2 ~ 3mmHg distillate to obtain 339.66g yellow oily liquid, namely, butylene phthalide (DBT-1).

References:

CN107216298,2017,A Location in patent:Paragraph 0057; 0058; 0059; 0066; 0067; 0068

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