Trifluoroacetic acid → HCID 24902685, compound
Reaction equation
Cl[C:2]1[CH:7]=[N:6][CH:5]=[CH:4][N:3]=1.FC(F)(F)C(O)=O.[OH:15][CH:16]1[CH2:19][N:18]([C:20]([O:22][C:23]([CH3:26])([CH3:25])[CH3:24])=[O:21])[CH2:17]1>>[N:3]1[CH:4]=[CH:5][N:6]=[CH:7][C:2]=1[O:15][CH:16]1[CH2:17][N:18]([C:20]([O:22][C:23]([CH3:26])([CH3:25])[CH3:24])=[O:21])[CH2:19]1Participants
4
Procedure
Compound P22 was prepared according to the general procedure described for the synthesis of P21 in Preparation 21, using 2-chloropyrazine in place of 2-bromopyridine, to afford P22. LCMS (ESI) m/z 252.4 (M÷1). 1H NMR (400 MHz, CDCl3) δ 1.43 (s, 9H), 3.97 (m, 2H), 4.32 (m, 2H), 5.30 (m, 1H), 8.03 (dd, J=2.5, 1.2 Hz, 1H), 8.16 (d, J=2.5 Hz, 1H), 8.26 (d, Hz, 1H). Compound P22 was deprotected with trifluoroacetic acid as described for tert-butyl 3-hydroxyazetidine-1-carboxylate in the preparation of C19 in Example 3, before being used in the coupling step.