24105-07-5Relevant articles and documents
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Eaton et al.
, p. 4071,4072 (1973)
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Grimaldi,Bertrand
, p. 3269,3270 (1969)
Cyclic ketones, their preparation and their use in the synthesis of amino acids
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, (2008/06/13)
A method is provided for making an enantiomerically pure of the formula: in which R and R′ represent C1?C10 alkyl, C2?C10 alkenyl or C3?C10 cycloalkyl and the wedges signify (S)- or (R)-stereochemistry, the substituents in compound (II) being trans. Conjugate addition is carried out between an organometallic nucleophile that provides a group R as defined above and (R)-4-acetoxycyclopent-2-en-1-one, (S)-4-acetoxycyclopent-2-en-1-one or a similar compound in which acetoxy is replaced by another leaving group to give, e.g. in the case of the acetoxy compound, a trans 3,4-disubstituted addition product of formula III or IV; The acetyl group is eliminated from the addition product to give an (R)- or (S)-4-alkyl or 4-alkenyl cyclopent-2-en-1-one the compound of formula is then to be hydrogenated to give a cyclopentanone of formula (I) or conjugate addition of a second organometallic nucleophile that provides a group R′ as defined above to the compound of the above formula may be carried out to give a trans 3,4-disubstituted addition product of formula (II). One of the above compounds may be converted e.g. via an intermediate (XV)-(XVIII) (in which the substituents R and R′ and the wedges have the meanings indicated above) to a gabapentin analogue of one of the formulae shown below: in which the substituents R and R′ and the wedges also have the meanings indicated above.
Synthesis of 2-Alkyl-2-cyclopenten-1-ones. A Versatile Kinetic Alkylation-Ozonolysis Procedure for the Preparation of γ-Ketoaldehydes
Geraghty, Niall W. A.,Morris, Noreen M.
, p. 603 - 607 (2007/10/02)
A range of 2-alkyl-2-cyclopenten-1-ones including the prostaglandin precursor 2-(6-methoxycarbonylhexyl)-2-cyclopenten-1-one and the jasmonoid precursor 2--2-cyclopenten-1-one, have been prepared by a short synthetic route which begins with 6-methyl-5-hepten-2-one and generates the key 1,4-ketoaldehyde intermediates by a kinetic alkylation-ozonolysis procedure.