Dess-Martin periodinate

Reaction of (S)-(+)-2-aminobutyrate hydrochloride with ethyl oxalyl chloride followed by replacing of the ethyl ester with amino alcohol, oxidation with Dess-Martin periodinate and cyclization using TFA/TFAA in acetic acid gave the cyclic product, which was further converted to the bromide. Sub-... 

Oxidation of 3-hydroxymethyl-2,3-dihydro-5H-pyrido[l,2,3-cfe][1,4] benzoxazin-5-ones with o-iodoxybenzoic acid in DMSO and with Dess-Martin periodinate in CH2CI2 afforded 3-formyl derivatives (08WOP2008/ 120003). Dehydrogenation of ethyl 10-[2-(ferf-butoxycarbonyl)-l,2,3,4,6,8a-hexahydropyrrolo[l,2-a]pyrazin-7-yl]-9-fluoro-3(S)-methyl-7-oxo-2,3-dihydro-7H-pyrido[l,2,3-de][l,4]oxazine-6-carboxylates in the presence of Pd/C with air in MeOH afforded 10-[2-(ferf-butoxycarbonyl)-l, 2,3,4-tetrahydropyrrolo[l,2-a]pyrazin-7-yl] derivatives, which then were deprotected (09BML4933). 

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