1: [(1,3-diphenylprop-2-yn-1-yl)oxy]acetic acid With O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate in dichloromethane 0.5 h; 2: O,N-dimethyl-hydroxylamine hydrochloride With N-ethyl-N,N-diisopropylamine in dichloromethane 2 h;

1: TBTU; (i-Pr)2NEt View Scheme

1.1: 1.38 g / aq. KOH / methanol / 16 h 2.1: [2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium]*BF4 / CH2Cl2 / 0.5 h 2.2: 80 percent / (i-Pr)2NEt / CH2Cl2 / 2 h View Scheme