反应详情

6′-Bromospiro[cyclobutane-1,2′-inden]-1′(3′H)-one (Intermediate 38, 1.1 g, 4.38 mmol), 2-methylpropane-2-sulfinamide (0.96 g, 7.88 mmol), and titanium ethoxide (1.805 mL, 8.76 mmol) were dissolved in methyl THF (20 mL), and heated to reflux overnight. The reaction was allowed to cool to r.t., then it was diluted with EtOAc (150 mL). Water (22 mL) was added dropwise over 10 min under vigorous stirring and then the mixture was left standing without stirring for 1.5 h. The solids were filtered off and the organics were evaporated to give a crude product which was purified by flash chromatography (eluent: heptane/ethylacetate 8:1) to afford the title compound (2.1 g, 77% yield), used as such in the next step: MS (ES+) m/z 354 [M+H]+.

1. temperatureheated
2. temperatureto reflux overnight
3. waitthe mixture was left
4. stirringwithout stirring for 1.5 h
5. filtrationThe solids were filtered off
6. customthe organics were evaporated
7. customto give a crude product which
8. customwas purified by flash chromatography (eluent: heptane/ethylacetate 8:1)