Monoalkyl oxiranes

Vvahrend Phenyl-oxiran hauptsachlich invers geoffnet wird, reagieren Monoalkyl-oxirane ahnlich wie mit ge-mischtcn Aluminiumhydriden hauptsachlich nach Markownikow6. 

The dianions of /S-enamino ketones react with a wide range of electrophiles such as alkyl halides, oxiranes, nitriles, esters, aldehydes and ketones37. Dalpozzo and coworkers reported the generation of the dianion derived from /S-enamino ketones with lithium 2,2,6,6-tetramethylpiperidide and the reaction of the dianion with nitroalkene (Scheme 24)38. The dianion underwent exclusive alkylation at the y-carbon atom to give the monoalkylated product in high yield. This reaction is useful for the introduction of a nitro group into a ketone side chain. 

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