tert-Butyl hydroperoxide → 1H-Indene-2-carboxylic acid, 5-chloro-2,3-dihydro-2-hydroxy-1-oxo-, methyl ester

Temperature

55 °C

A chiral zirconium complex was prepared by stirring zirconium(IV) isopropoxide (0.0345 g, 0.089 mmol) with 2,2′-[(1S,2S)-1,2-cyclohexanediylbis(iminomethylene)]bis[4,6-bis(1,1-dimethylethyl)phenol] (Formula IIIa wherein R6 is C(CH3)3, 0.0613 g, 0.11 mmol) in toluene (2 mL) at ambient temperature. After stirring overnight, the homogeneous solution was evaporated to dryness in vacuo, and the residue redissolved in toluene (1.34 g). Methyl 5-chloro-2,3-dihydro-1-oxo-1H-indene-2-carboxylate (0.250 g, 1.11 mmol) (Formula IIa wherein R1 is OCH3 and R4 is Cl) was added to the toluene solution, the solution was heated to 55° C., and then an aqueous solution of tert-butyl hydroperoxide (70%, 0.316 g, 2.46 mmol) was added. After 2 hours at 55° C., the solution was diluted with acetonitrile (11.5 mL). Analysis by quantitative and chiral HPLC showed 100% conversion of methyl 5-chloro-2,3-dihydro-1-oxo-1H-indene-2-carboxylate, forming methyl 5-chloro-2,3-dihydro-2-hydroxy-1-oxo-1H-indene-2-carboxylate in 84% yield (84% chemoselectivity) and 84% enantiomeric excess of the S-enantiomer.

1. customA chiral zirconium complex was prepared
2. customthe homogeneous solution was evaporated to dryness in vacuo
3. dissolutionthe residue redissolved in toluene (1.34 g)
4. waitAfter 2 hours at 55° C.

ORD record

ord-5790238f2a5b495085c121124b7d8105

Source dataset

uspto-grants-2010_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07718818B2