Alkylation with benzyloxymethyl chloride

Alternatively, aldehyde 589 can be obtained from lactamide 6c by alkylation with benzyloxymethyl chloride, which gives 590 with absolutely no racemization, followed by reduction of the amide with Vitride [95]. 

The asymmetric synthesis of 2-mono- and 2,3-/rtjw5-disubstituted azetidines 3 has been described <04EJO4471>. Key steps are a diastereoselective a-alkylation of aldehyde SAMP-hydrazones with benzyloxymethyl chloride as the electrophile, and a nucleophilic 1,2-... 

As is depicted in Scheme 1.2.29, the epoxide 128 was synthesized starting from 2,2-dimethyl-l,3-dioxan-5-one RAMP hydrazone (R)-96, which was double-alkylated with methyl iodide at a- and a -positions leading to the trons-dimethylated hydrazone 131 in 79% yield over two steps and excellent stereoselectivity (de, ee > 96%) [68]. The quaternary stereocenter bearing the desired tertiary alcohol function was generated using benzyloxymethyl chloride (BOMCl) as the electrophile to trap the lithiated hydrazone 131, providing the a-quaternary hydrazone 132 in very good yield (92%), excellent diastereomeric and enantiomeric excesses (de, ee > 96%) and with the required cis relationship of the methyl substituents. 

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