intermediate.JPG

Objective

To isolate and characterize a boc-deprotected intermediate from a Ugi product that was synthesized here.

Procedure

Prepared 10% TFA solution by adding 100uL TFA to 1mL volumetric flask. Diluted to mark with 1,2-dichloroethane. Added 50mg Ugi Product (62E) to flask. Allowed reaction to sit for 30 mins. Washed organic layer with water. Removed water layer. Added 10mL saturated NaOH solution. Added methylene chloride and extracted in separatory funnel. Took NMR spectra.

Results

Ugi Product
62E

90B
HNMR

Discussion

Based on prior experiments how long would you need to expose the Ugi product to 10%TFA in CDCl3 to completely lose the boc group?

Conclusion



Log

2007-04-09

11:52 Weighed out 50mg Ugi Product (62E).
12:09 Added 100ul TFA and diluted to mark with 1,2 DCE.
12:46 Washed with water (how much?). Separated water layer.
15:30 Added 10mL NaOH to water layer.

2007-04-12

11:46 Transfered contents to extraction funnel. Added 10mL methylene chloride. Shook vigorously, allowed layers to separate and removed organic layer. Repeated twice.
12:53 Placed organic layer in a round bottom fladk. Evaporated off solvent using rotovap.
13:45 Some difficulty getting solvent to evaporate. Placed on high vac.
14:10 Solvent evaporated. Removed from high vac. Saw white solid at bottom of flask.
14:20 Added 800uL deuterated chloroform. White solid didn't readily dissolve. Took NMR. Solution yellow (90B). You always have to add MgSO4 and filter after an extraction - take what you have in some more MC, add MgSO4 then filter, evaporate and report weight and NMR as 90C

Tags

UgiproductInChI=1/C26H35N3O7/c1-16-8-10-18(35-16)14-29(21(30)13-27-24(32)36-26(5,6)7)22(23(31)28-25(2,3)4)17-9-11-19-20(12-17)34-15-33-19/h8-12,22H,13-15H2,1-7H3,(H,27,32)(H,28,31)
Freeamine:InChI=1/C21H27N3O5/c1-13-5-7-15(29-13)11-24(18(25)10-22)19(20(26)23-21(2,3)4)14-6-8-16-17(9-14)28-12-27-16/h5-9,19H,10-12,22H2,1-4H3,(H,23,26)



external image Exp065&js=1&rnd=0.7256575166237567