Allyl organometallic compounds 1,3-asymmetric induction

Yamamoto and coworkers [3], however, have reported that reactions of al-lyl-9-BBN with certain chiral imines give the corresponding allylation products with very high enantiomeric excess, in essentially, the quantitative yields (Eq. 12.2). Table 12.1 summarizes these very high 1,2-asymmetric inductions. The main reason for poor selectivity of imine is the complex reactivity of imines toward other organometallic compounds [4-6]. 

The 1,2-asymmetric induction with crotyl organometallic compounds (M = B, Zr, and Mg) is not so high as with the allyl system. The reaction of crotylorgano-metal with 3 (R = n-Pr and i-Pr) produces all the possible four isomers. 

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