exp072

= = =Objective= To cyclize a [|Ugi product] to form a [|diketopiperazine] via a [|boc-deprotected intermediate]. This [|Ugi product] was synthesized here. = = =Procedure= Prepared 10% HCl solution by adding 100uL concentrated (12 M) aqueous HCl to 1mL volumetric flask. Diluted to mark with deuterated methanol. Took NMR spectra. Added 50mg Ugi Product ([|62E]) to NMR tube and monitored reaction via NMR spectra at specific intervals.

=Results= 10% HCl Solution [|HNMR]

62E [|HNMR]

10%HCl/ Ugi Product [|HNMR]

Reflux TAR= 30min [|HNMR]

TAR= 90 min [|HNMR]

TAR= 150 min [|HNMR]

=Discussion= 1. The methyl group is still present at 2.2ppm. 2. It is hard to discern whether the boc group was lost even though a small peak at 1.6ppm begins to appear. 3. Some side reactions may be occuring with the appearance of new peaks at 1.29ppm - 1.38 ppm. 4. The doublets at 8.743 ppm and 4.477 point towards a clear **'Furfuryl cleavage**'. This is the first time this type of cleavage has ever been observed in 10% HCl.- Khalid

=Conclusion= The Ugi product did not cyclize. Fufuryl cleavage observed for the first time in a tertiary amide.

=Log=

2007-03-23
11:20 Set temperature bath to 65C. Prepared 10% HCL solution. 11:32 Attempted NMR spectra. Had problems getting the NMR to lock and spin consistently.

2007-03-26
11:17 Prepared 800uL 10% HCl solution. Took NMR spectra. Set temperature bath to 65C. 12:01 Weighed out 50 mg of 62E and added it to contents of NMR tube. 12:15 Some problems with getting the crystals to dissolve. Added 20uL deuterated chloroform. 12:22 Crystals completely dissolved. Took NMR spectra. 12:46 Unable to get spectra until 12:37. Placed NMR tube in temperature bath. Bath temperature 60C. 12:52 Bath temperature 64C. Noticed condensation in the flask. 13:05 Bath temperature 70C. Reaction turned yellow. 13:30 Bath temperature 70C. Reaction turned orange. Took NMR spectra. 13:44 Bath temperature 70C. Returned reaction flask to temperature bath. 14:11 Bath temperature 70C. Took NMR spectra. Solution turned deep orange. 14:34 Bath temperature 70C. Placed NMR tube in bath. 15:30 Bath temperature 70C. Took NMR spectra. Solution turned red.

=Tags= [|Ugiproduct][|InChI=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,28,3]1) [|DKP065] [|InChI=1/C17H16N2O5/c1-10-2-4-12(24-10)8-19-15(20)7-18-17(21)16(19)11-3-5-13-14(6-11)23-9-22-13/h2-6,16H,7-9H2,1H3,(H,18,21)]