Reaction #3863

Reaction equation

Piperidine

Methane sulfonyl chloride

product

6-Methoxy-4-hydroxy-2,3-dihydrobenzopyran

sodium bicarbonate

→

desired product

6-Methoxy-4-piperidino-2,3-dihydrobenzopyran

Solvents

methylene chloride

triethylamine

Conditions

Workup

1. 1
   Temperaturecooled to 0° C
2. 2
   workup.STIRRINGthe solution stirred at RT overnight
3. 3
   workup.STIRRINGthe mixture is stirred for 30 minutes
4. 4
   OtherThe organic layer is separated
5. 5
   Washwashed with sat'd NaCl
6. 6
   Otherdried
7. 7
   FiltrationThe solution is filtered
8. 8
   Otherthe filtrate evaporated in vacuo

Procedure

Methane sulfonyl chloride (14.9 ml) is added dropwise to a stirred solution of the product obtained in Step 1. (31.6 g) and triethylamine (29.3 ml) in methylene chloride (750 ml) cooled to 0° C. under nitrogen. The reaction mixture is stirred at RT for 21/2 hours and cooled to 0° C. Piperidine (175 ml) is added to the cooled reaction mixture and the solution stirred at RT overnight. Sat'd aq. sodium bicarbonate is added to the solution and the mixture is stirred for 30 minutes. The organic layer is separated, washed with sat'd NaCl and dried. The solution is filtered and the filtrate evaporated in vacuo yielding the desired product as its hydrochloride salt.

Source