Practical Synthesis of Chiral Emopamil Left Hand as a Bioactive Motif
摘要:
An asymmetric synthesis of (2S)-2-(2-isopropyl)-5-hydroxy-2-phenylpentanenitrile (emopamil left hand, 2) has been completed by use of the MAD (methyl aluminum bis(4-methyl-2,6-di-tert-butylphenoxide)-induced rearrangement of a chiral epoxyalcohol as the key reaction. The stereochemistry of the chiral quaternary center was confirmed by transformation of 2 to (S)-noremopamil. This method requires minimal purification procedures and affords high chemical and optical yields. Acid-catalyzed isomerization of an allylaldehyde and retro-aldol type racemization at the quaternary carbon of a nitrile-alcohol were encountered.
Practical Synthesis of Chiral Emopamil Left Hand as a Bioactive Motif
摘要:
An asymmetric synthesis of (2S)-2-(2-isopropyl)-5-hydroxy-2-phenylpentanenitrile (emopamil left hand, 2) has been completed by use of the MAD (methyl aluminum bis(4-methyl-2,6-di-tert-butylphenoxide)-induced rearrangement of a chiral epoxyalcohol as the key reaction. The stereochemistry of the chiral quaternary center was confirmed by transformation of 2 to (S)-noremopamil. This method requires minimal purification procedures and affords high chemical and optical yields. Acid-catalyzed isomerization of an allylaldehyde and retro-aldol type racemization at the quaternary carbon of a nitrile-alcohol were encountered.
Metallophthalocyanine complex, Cr(TBPC)OTf: an efficient, recyclable Lewis acid catalyst in the regio- and stereoselective rearrangement of epoxides to aldehydes
The metallophthalocyanine complex Cr(TBPC)OTf works as a highly efficient, recyclable Lewisacidcatalyst for the regio- and stereoselective rearrangements of epoxides to aldehydes.
characteristic Lewis acid catalyst in the regio- and stereoselective rearrangement of epoxides to aldehydes. This Cr(TPP)OTf-catalyzed reaction is an operationally simple and especially convenient method for synthesizing optically active beta-siloxy aldehydes from 2,3-epoxy silyl ethers which are readily available in enantiomerically enriched forms by the Sharpless epoxidation of allylic alcohols followed
An asymmetric synthesis of (2S)-2-(2-isopropyl)-5-hydroxy-2-phenylpentanenitrile (emopamil left hand, 2) has been completed by use of the MAD (methyl aluminum bis(4-methyl-2,6-di-tert-butylphenoxide)-induced rearrangement of a chiral epoxyalcohol as the key reaction. The stereochemistry of the chiral quaternary center was confirmed by transformation of 2 to (S)-noremopamil. This method requires minimal purification procedures and affords high chemical and optical yields. Acid-catalyzed isomerization of an allylaldehyde and retro-aldol type racemization at the quaternary carbon of a nitrile-alcohol were encountered.