Aldol reaction in nature

The Aldol Reaction in Natural Product Synthesis The Epothilone Story... 

Stereoselective Aldol Reactions in Nature and in the Laboratory Organocatalysis ... 

Updated coverage of stereoselective aldol reactions in nature and in the laboratory Organocatalysis (Ch. 18)... 

A number of other valuable aroma chemicals can be isolated from essential oils, eg, eugenol from clove leaf oil, which can also, on treatment with strong caustic, be isomerked to isoeugenol, which on further chemical treatment can be converted to vanillin (qv). Sometimes the naturally occurring component does not requke prior isolation or concentration, as in the case of cinnamaldehyde in cassia oil which, on dkect treatment of the oil by a retro-aldol reaction, yields natural ben2aldehyde (qv). This product is purified by physical means. 

Compound a-vinyl-/ -hydroxyimdide 21, which can be used in the total synthesis of natural products, can be prepared through aldol reaction. In most cases of aldol reactions mediated by 21, products of more than 98% de can be obtained (Scheme 3-8).12... 

I. Paterson C. J. Cowden, D. J. Wallace, Stereoselektive Aldol Reactions in the Synthesis of Polyketide Natural Products, in Modem Carbonyl Chemistry, Ed. J. Otera, Wiley-VCH, Weinheim, 2000, 249-297. 

The directed aldol reaction in the presence of TiC found many applications in natural product synthesis. Equation (7) shows an example of the aldol reaction utilized in the synthesis of tautomycin [46], in which many sensitive functional groups survived the reaction conditions. The production of the depicted single isomer after the titanium-mediated aldol reaction could be rationalized in terms of the chelation-controlled (anft-Felkin) reaction path [37]. A stereochemical model has been presented for merged 1,2- and 1,3-asymmetric induction in diastereoselective Mukaiyama aldol reaction and related processes [47]. 

Stereoselective Aldol Reactions in the Synthesis of Polyketide Natural Products... 

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