o-nitro-benzaldoxime; N,N,N',N'-tetramethylguanidine in acetonitrile T=20°C; 3 h;

1.1: 86 percent / imidazole / dimethylformamide / 12 h / 20 °C 2.1: aq. Na2CO3; tetrabutylammonium bromide; 2,4,6-triisopropylbenzenesulfonyl chloride / CH2Cl2 / 20 °C 2.2: 89 percent / Et3N; 1,4-diazabicyclo[2,2,2]octane / acetonitrile / 3 h / 20 °C 3.1: Lawesson's reagent / toluene / 2 h / Heating 4.1: 78 percent / tetrabutylammonium fluoride; acetic acid / tetrahydrofuran / 20 h / 20 °C 5.1: 80 percent / 1,1,3,3-tetramethylguanidine; syn-o-nitrobenzaldoxime / acetonitrile / 3 h / 20 °C View Scheme

1.1: aq. Na2CO3; tetrabutylammonium bromide; 2,4,6-triisopropylbenzenesulfonyl chloride / CH2Cl2 / 20 °C 1.2: 89 percent / Et3N; 1,4-diazabicyclo[2,2,2]octane / acetonitrile / 3 h / 20 °C 2.1: Lawesson's reagent / toluene / 2 h / Heating 3.1: 78 percent / tetrabutylammonium fluoride; acetic acid / tetrahydrofuran / 20 h / 20 °C 4.1: 80 percent / 1,1,3,3-tetramethylguanidine; syn-o-nitrobenzaldoxime / acetonitrile / 3 h / 20 °C View Scheme

1: Lawesson's reagent / toluene / 2 h / Heating 2: 78 percent / tetrabutylammonium fluoride; acetic acid / tetrahydrofuran / 20 h / 20 °C 3: 80 percent / 1,1,3,3-tetramethylguanidine; syn-o-nitrobenzaldoxime / acetonitrile / 3 h / 20 °C View Scheme

1: 78 percent / tetrabutylammonium fluoride; acetic acid / tetrahydrofuran / 20 h / 20 °C 2: 80 percent / 1,1,3,3-tetramethylguanidine; syn-o-nitrobenzaldoxime / acetonitrile / 3 h / 20 °C View Scheme