Ethylenediamine → N-methyl-N-(3-styryl-1H-indazol-6-yl)-benzene-1,3-diamine

To N-methyl-N-{3-styryl-1-[2-(trimethyl-silanyl)-ethoxymethyl]-1H-indazol-6-yl}-benzene-1,3-diamine (237 mg, 0.5 mmol) was added 1M TBAF in THF (10.1 mL, 10.1 mmol), followed by ethylenediamine (0.34 mL, 5.04 mmol, 10 equiv). The resulting mixture was heated to 70° C. for 5 h. The reaction was then quenched with saturated NaHCO3 (10 mL) and extracted 3×35 mL EtOAc. The pooled EtOAc phase was washed 5×20 mL H2O, then brine (20 mL), dried with Na2SO4, decanted and concentrated under reduced pressure to a foam. The crude material was purified by silica gel chromatography (9:1 dichloromethane/ethyl acetate) to give N-methyl-N-(3-styryl-1H-indazol-6-yl)-benzene-1,3-diamine as a foam (120 mg, 70% yield). Rfsm 0.73, Rfp 0.27 (dichloromethane:ethylacetate 7:3); 13C NMR (75 MHz, CDCl3) δ 150.3, 148.8, 147.5, 147.5, 143.9, 143.4, 137.5, 131.1, 130.3, 129.3, 128.9, 128.2, 127.9, 126.7, 121.0, 120.5, 117.0, 116.0, 112.6, 109.8, 109.0, 98.3, 40.7; LCMS (ESI) [M+H]/z Calc'd 341, Found 341. Anal. Calc'd: C, 77.62; H, 5.92; N, 16.46. Found: C, 76.16; H, 5.88; N, 15.95.

1. customThe reaction was then quenched with saturated NaHCO3 (10 mL)
2. extractionextracted 3×35 mL EtOAc
3. washThe pooled EtOAc phase was washed 5×20 mL H2O
4. dry with materialbrine (20 mL), dried with Na2SO4
5. customdecanted
6. concentrationconcentrated under reduced pressure to a foam
7. customThe crude material was purified by silica gel chromatography (9:1 dichloromethane/ethyl acetate)

ORD record

ord-624b1d89fc67467c8d6f5360ebaa1a13

Source dataset

uspto-grants-2003_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06534524B1