Page 123 - Catalysts for Fine Chemical Synthesis Vol 1 - Robert & Poignant
P. 123
Catalysts for Fine Chemical Synthesis: Hydrolysis, Oxidation and Reduction. Volume 1
Edited by Stan M Roberts and Geraldine Poignant
Copyright 2002 John Wiley & Sons, Ltd.
ISBN: 0-471-98123-0
8 Asymmetric Sulfoxidation
CONTENTS
8.1 Asymmetric oxidation of sulfides and kinetic resolution of sulfoxides
Laura Palombi and Arrigo Scettri . . . . . . . . . . . . . . 109
8.1.1 Asymmetric oxidation of 4-bromothioanisole . . . . . . . . . . 109
8.1.2 Kinetic resolution of racemic 4-bromophenyl methyl sulfoxide . . . . . 111
References . . . . . . . . . . . . . . . . . . . . . . . 113
8.1 ASYMMETRIC OXIDATION OF SULFIDES AND KINETIC
RESOLUTION OF SULFOXIDES
Laura Palombi and Arrigo Scettri
Dipartimento di Chimica, Universita di Salerno, 84081 Baronissi (Salerno), Italy
8.1.1 ASYMMETRIC OXIDATION OF 4-BROMOTHIOANISOLE
RO 2 C
O RO 2 C
S S
+
Me Me Ti(IV)/ L-DET Me +
Me O Me
Me O
OOH Br CH 2 Cl 2 , −208C Br OH
1 2 (R)-3 4
R: Cholestanyl
Materials and equipment
. Anhydrous dichloromethane (99.8 %), 3.5 mL
. 4-Bromothioanisole (97 %), 61 mg, 0.3 mmol
. Titanium(IV) isopropoxide (97 %), 0.09 mL, 0.3 mmol
. Diethyl l-tartrate (99 %), 0.21 mL, 1.2 mmol
. 5-(1-Hydroperoxyethyl)-2-methyl-3-furoic acid 5a-cholestan-3b-yl ester
(1)[1c] (mixture of diastereo-isomers), 171 mg, 0.3 mmol
. Ethyl acetate, n-hexane
. Anhydrous sodium sulfate
