Jacobsen‐Type Enantioselective Hydrolysis of Aryl Glycidyl Ethers. ³¹P NMR Analysis of the Enantiomeric Composition of Oxiranes.

Abstract

Enantioselective syntheses Enantioselective syntheses O 0031Jacobsen-Type Enantioselective Hydrolysis of Aryl Glycidyl Ethers. 31 P NMR Analysis of the Enantiomeric Composition of Oxiranes. -Efficient kinetic resolution of racemic aryl glycidyl ethers (I) is achieved by enantioselective partial hydrolysis in the presence of chiral Co III (salen) catalyst. Chiral diols (IIb) and (IIc) thus obtained are used for the efficient preparation of the β-adrenoblocking agents (S)-toliprolol (Vb) and (S)-moprolol (Vc), respectively. -(BREDIKHIN*, A. A.; STRUNSKAYA, E. I.; NOVIKOVA, V. G.; AZANCHEEV, N. M.; SHARAFUTDINOVA, D. R.; BREDIKHINA, Z. A.; Russ.

Jacobsen Enantioselective Hydrolysis of Glycidyl Diethyl Phosphate

“…The 1 H (400 MHz), 13 C (100.6 MHz), and 31 P (162.0 MHz) NMR spectra were recorded from CDCl 3 solutions. The conditions of recording the NMR and mass spectra were similar to those described in [4].…”

“…The reaction mixture after treatment with petroleum ether was fractionated to separate (S)-diethyl phosphate and (R)-glycidyl diethyl 2,3-dihydroxy- Measuring enantiomeric purity. The enantiomeric excess (ee) of glycidyl phosphate (S)-I was measured by 31 P NMR spectroscopy with (4R,5R)-bis-(N,N-dimethylaminocarbonyl)-2-chloro-1,3,2-dioxaphospholane IV according to [4]. A fragment of the 31 P NMR spectrum of the derivatized reaction mixture is as follows, d P , ppm (I): 140.00 (1.00) and 140.61 (0.08); hence, ee = [(1.00 3 0.08)/(1.00 + 0.08)] 0 100 = 85%.…”

“…We applied this reaction to a wide set of aryl glycidyl ethers [4] and obtained a series of known b-adrenoblocators as pure enantiomers. In the series of phosphorus-substituted oxiranes, enantioselective hydrolysis was applied previously to kinetic separation of diethyl oxiranylphosphonate [5].…”