3-Heptanone, 5-hydroxy-2,4,6-trimethyl-2-

Halide exchange reaction, 66, 87 2,5-Heptadien-4-ol, 3,4,5-trimethyl-, 65, 42 Heptanal (111-71-7), 65, 26 3-HEPTANONE, 4-METHYL-, (S)-, 65, 183 5-Heptynoic acid, 7-hydroxy-, methyl ester, 67, 193... 

It has been suggested that the 1.3-asymmetric induction is the result of a chairlike cyclic transition state 3, in which the stereodirecting group R1 adopts an equatorial orientation. One feature of this transition state is that the orientation of a substituent a to the carbonyl group should not greatly affect the energy. In accord with this hypothesis, it was found that both isomers of 5-hydroxy-2,4,6-trimethyl-3-heptanone led to the same f/-l,3-diols with excellent d.r. (Table l)s. 

Dimethyl- 3-pentanone Enolate 5-Hydroxy-2,2,4-trimethyl-3-heptanone (81%)... 

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