Organocerium reagents, reaction with

Amides, especially of piperidine and morpholine, give good yields of ketones on reaction with organocerium reagents.203 It has been suggested that the morpholine oxygen may interact with the oxyphilic cerium to stabilize the addition intermediate. 

In the study of Weber et al.,41 a series of proline-derived hydrazones were prepared, and the reactions of the hydrazones with organocerium reagents were examined. It is clear from the table in Scheme 2 24 that the diastereoselectivity of the examined reactions depends on the nature of the side chain. (S )-l-amino-2-(2-methoxyethoxymethyl) pyrrolidine (40) gave the highest selectivity for various nucleophiles. 

Recently, Mudryk and Cohen have found that reactions of lactones with organocerium reagents provide lactols in go yields, as exemplified in Scheme 10. This reactiim leads to an efficient (xie-pot synthesis of spiroketais, as illustrated in Scheme 11. ... 

Table 1 The Reaction of Organocerium Reagents with Ketones...

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