formic acid; dihydrogen peroxide

1.1: triphenylphosphine / dichloromethane / 0.5 h / 0 °C 1.2: 3 h / 0 °C 2.1: tert.-butyl lithium / tetrahydrofuran / -78 - 20 °C 3.1: methanesulfonic acid; 2-bromopyridine N-oxide; C45H57AuF6NO9PS2 / chloroform / 0.5 h / 60 °C View Scheme

sodium hydroxide; benzo-15-crown-5 in water; toluene T=90°C; 6 h; further phase-transfer catalysts; also 2-methylindan-1,3-dione with other methylating agents; Product distribution;