199383-77-2Relevant academic research and scientific papers
Desymmetrisation of 4,4-disubstituted cyclohexanones by enzyme-catalysed resolution of their enol acetates
Allan, Graham,Carnell, Andrew J.,Hernandez, Maria Luisa Escudero,Pettman, Alan
, p. 3382 - 3388 (2007/10/03)
Enol acetates 3 10 derived from prochiral 4,4-disubstituted cyclohexanones can be resolved with Pseudomonas fiuorescens lipase to give enantiomerically pure (>99% ee) enol esters by transesterification with n-BuOH. The product ketones are prochiral and can easily be recycled giving an overall desymmetrisation of the ketone. Highest selectivity was obtained for substrates containing a 4-cyano and 4-aryl or a 4-benzyloxy substituent. The methodology was compared to asymmetric deprotonation-enolate trapping using the chiral base (S,S)-bis(α-methylbenzyl)amide which gave low (54-64%) ee's for this class of ketones.
Chemoenzymatic synthesis of a non-peptide tachykinin NK-2 antagonist
Carnell, Andrew J.,Hernandez, Maria Luisa Escudero,Pettman, Alan,Bickley, Jamie F.
, p. 6929 - 6933 (2007/10/03)
The synthesis of a tachykinin NK-2 antagonist (S)-11 has been carried out in four steps starting from the the (S)-(+)-enol acetate 3, which was obtained in 100% e.e. by resolution of the racemic ester with Pseudomonas fluorescens lipase. The absolute configuration of the enol acetate (+)-3 was confirmed by X-ray analysis of the camphanyl derivative 13. (C) 2000 Elsevier Science Ltd.
Desymmetrisation of prochiral ketones by catalytic enantioselective hydrolysis of their enol esters using enzymes
Carnell, Andrew J.,Barkley, Jim,Singh, Amarjit
, p. 7781 - 7784 (2007/10/03)
Desymmetrisation of 4-cyano-4-phenylcyclohexanone 1 has been achieved by enzyme-catalysed enantioselective alcoholysis with n-butanol of the derived racemic enol acetate 2 in tetrahydrofuran. The absolute configuration of the enol aceate (-)-(S)-2 (100% e.e.) obtained was determined by X-ray analysis of the camphanyl derivative 7.
