Robinson anellation

Michael additions of C-nudeophiles such as the indanone 1 have been the subject of numerous further studies For example, the reaction between the indanone 1 and methyl vinyl ketone was effected by a solid-phase-bound quinine derivative in 85% yield and with remarkable 87% ee by d Angelo, Cave et al. [5], Co-polymers of cinchona alkaloids with acrylonitrile effected the same transformation Kobaya-shi and Iwai [6a] achieved 92% yield and 42% ee and Oda et al. [6b] achieved almost quantitative yield and up to 65% ee. Similarly, partially resolved 2-(hydroxy-methyl)quinudidine was found to catalyze the reaction between 1 and acrolein and a-isopropyl acrolein with induction of asymmetry, but no enantiomeric excesses were determined [7]. As shown in Scheme 4.4, the indanone 7 could be added to MVK with up to 80% ee under phase-transfer conditions, by use of the Cinchona-derived PT-catalysts 9a and 9b, affording the Michael-product 8 or enf-8, respectively [8]. The adducts 8 or ent-8 were intermediates in the stereoselective Robinson anellation of a cydohexenone ring to the indanone 7 [8],... 

Buten-2-one (methyl vinyl ketone) pr., 174 cyclopropanated silyl enolate rearrs., 77 diene addition to, 212, 297 Michael addition to, 205 Robinson anellation with, 72-73, 211-212,298 —, 4-methoxy- pr., 176... 

C-nucIeophilicity, 13-14 oxidative cleavage, 285 Robinson anellation of, 73, 298 synthesis from ketones, 13, 88 by oxn. of ten. amines, 138-139 Enantiofaces definition, 359... 

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