The Experts below are selected from a list of 3 Experts worldwide ranked by ideXlab platform
David Ohagan - One of the best experts on this subject based on the ideXlab platform.
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chiral fluoroacetic acid synthesis of r and s 2h1 Fluoroacetate in high enantiopurity
Tetrahedron-asymmetry, 2013Co-Authors: Rudy D P Wadoux, Xiaowei Lin, Neil S Keddie, David OhaganAbstract:Abstract A two-step synthesis of ( R )- and ( S )-[ 2 H 1 ]-Fluoroacetate (Sodium salts) in high enantioselectivity is reported. The synthesis is the development of a previous one in which the enantioselectivity has been increased from ∼38% ee to >95% ee. The improvement in enantioselectivity applied Bio’s methodology, which involved a deoxyfluorination reaction with DAST on either enantiomer of [ 2 H 1 ]-benzyl alcohol, adding TMS-morpholine to the reaction. The additive promotes an S N 2 inversion process, and suppresses a competing non-stereospecific S N 1 reaction course, and as a result significantly improves the stereointegrity of the C–F bond formation. The intermediate [ 2 H 1 ]-benzyl alcohols, [ 2 H 1 ]-benzyl fluorides and the product [ 2 H 1 ]-Fluoroacetates as their hexyl esters were separately assayed for their stereochemical integrity, using the Courtieu method. This method involved measuring their 2 H NMR spectra in a chiral matrix of poly -γ-benzyl l -glutamate. The chiral assay demonstrated that there was no significant loss in stereointegrity during the deoxyfluorination reaction and showed that the enantiomers of [ 2 H 1 ]-Fluoroacetate were generated with high enantiomeric purity (95% ee).
Xiaowei Lin - One of the best experts on this subject based on the ideXlab platform.
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chiral fluoroacetic acid synthesis of r and s 2h1 Fluoroacetate in high enantiopurity
Tetrahedron-asymmetry, 2013Co-Authors: Rudy D P Wadoux, Xiaowei Lin, Neil S Keddie, David OhaganAbstract:Abstract A two-step synthesis of ( R )- and ( S )-[ 2 H 1 ]-Fluoroacetate (Sodium salts) in high enantioselectivity is reported. The synthesis is the development of a previous one in which the enantioselectivity has been increased from ∼38% ee to >95% ee. The improvement in enantioselectivity applied Bio’s methodology, which involved a deoxyfluorination reaction with DAST on either enantiomer of [ 2 H 1 ]-benzyl alcohol, adding TMS-morpholine to the reaction. The additive promotes an S N 2 inversion process, and suppresses a competing non-stereospecific S N 1 reaction course, and as a result significantly improves the stereointegrity of the C–F bond formation. The intermediate [ 2 H 1 ]-benzyl alcohols, [ 2 H 1 ]-benzyl fluorides and the product [ 2 H 1 ]-Fluoroacetates as their hexyl esters were separately assayed for their stereochemical integrity, using the Courtieu method. This method involved measuring their 2 H NMR spectra in a chiral matrix of poly -γ-benzyl l -glutamate. The chiral assay demonstrated that there was no significant loss in stereointegrity during the deoxyfluorination reaction and showed that the enantiomers of [ 2 H 1 ]-Fluoroacetate were generated with high enantiomeric purity (95% ee).
Rudy D P Wadoux - One of the best experts on this subject based on the ideXlab platform.
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chiral fluoroacetic acid synthesis of r and s 2h1 Fluoroacetate in high enantiopurity
Tetrahedron-asymmetry, 2013Co-Authors: Rudy D P Wadoux, Xiaowei Lin, Neil S Keddie, David OhaganAbstract:Abstract A two-step synthesis of ( R )- and ( S )-[ 2 H 1 ]-Fluoroacetate (Sodium salts) in high enantioselectivity is reported. The synthesis is the development of a previous one in which the enantioselectivity has been increased from ∼38% ee to >95% ee. The improvement in enantioselectivity applied Bio’s methodology, which involved a deoxyfluorination reaction with DAST on either enantiomer of [ 2 H 1 ]-benzyl alcohol, adding TMS-morpholine to the reaction. The additive promotes an S N 2 inversion process, and suppresses a competing non-stereospecific S N 1 reaction course, and as a result significantly improves the stereointegrity of the C–F bond formation. The intermediate [ 2 H 1 ]-benzyl alcohols, [ 2 H 1 ]-benzyl fluorides and the product [ 2 H 1 ]-Fluoroacetates as their hexyl esters were separately assayed for their stereochemical integrity, using the Courtieu method. This method involved measuring their 2 H NMR spectra in a chiral matrix of poly -γ-benzyl l -glutamate. The chiral assay demonstrated that there was no significant loss in stereointegrity during the deoxyfluorination reaction and showed that the enantiomers of [ 2 H 1 ]-Fluoroacetate were generated with high enantiomeric purity (95% ee).
Neil S Keddie - One of the best experts on this subject based on the ideXlab platform.
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chiral fluoroacetic acid synthesis of r and s 2h1 Fluoroacetate in high enantiopurity
Tetrahedron-asymmetry, 2013Co-Authors: Rudy D P Wadoux, Xiaowei Lin, Neil S Keddie, David OhaganAbstract:Abstract A two-step synthesis of ( R )- and ( S )-[ 2 H 1 ]-Fluoroacetate (Sodium salts) in high enantioselectivity is reported. The synthesis is the development of a previous one in which the enantioselectivity has been increased from ∼38% ee to >95% ee. The improvement in enantioselectivity applied Bio’s methodology, which involved a deoxyfluorination reaction with DAST on either enantiomer of [ 2 H 1 ]-benzyl alcohol, adding TMS-morpholine to the reaction. The additive promotes an S N 2 inversion process, and suppresses a competing non-stereospecific S N 1 reaction course, and as a result significantly improves the stereointegrity of the C–F bond formation. The intermediate [ 2 H 1 ]-benzyl alcohols, [ 2 H 1 ]-benzyl fluorides and the product [ 2 H 1 ]-Fluoroacetates as their hexyl esters were separately assayed for their stereochemical integrity, using the Courtieu method. This method involved measuring their 2 H NMR spectra in a chiral matrix of poly -γ-benzyl l -glutamate. The chiral assay demonstrated that there was no significant loss in stereointegrity during the deoxyfluorination reaction and showed that the enantiomers of [ 2 H 1 ]-Fluoroacetate were generated with high enantiomeric purity (95% ee).