Oxadiazepine derivatives

Reaction of perfluoro-5-azanon-4-ene with the amino alcohols 296 in the presence of base affords a convenient route to the oxadiazepine derivatives 297a,b [01JFC11]. 

The reaction of acenaphthenequinone monohydrazone (92) with diethyl ethynedicarboxylate in boiling tetrahydrofuran gave the fully unsaturated fused 1,4,5-oxadiazepine derivative (93) (12% yield), together with two other products (Equation (3)) <72IJC875>. 

A facile route to l,3,4-oxadiazepin-2-ones has been developed by Komatsu et al. involving acid-catalysed cyclisation of carbazate derivatives derived from the reaction of N, A -di-tert-butyldiaziridinone and a-hydroxy ketones with BF3.Et20 catalysis <00H(52)541>. 

The total synthesis of the fused 1,2,5-oxadiazepine 60 was carried out commencing from 5-hydroxyisophthalic acid and L-diethyl tartrate (Scheme 49). The key intermediate 33 for the synthesis of 60 was obtained from 222, the triacetyl derivative of 60 <1996TL3471, 1996TL3479, 1997T10229, 1997T10253>. 

Krakowiak, K. E. (1982) Synthesis of New S-10 Member Heterocyclic Systems Perhydro-1,4,6-oxadiazocine, Perhydro-1,4,7-oxadiazecine, Perhydro-l,5.7-oxadiazecine- and New Derivatives of Perhydro-1,4,5-oxadiazepine, Ph.D. thesis. Medical Academy, Lodz, Poland. 

Curtius rearrangement of the azidocarbonylpyrazoles (103) afforded the pyrazolo[l,5-e]-l,3,5-oxadiazepines (104) (55-77% yields) by an intramolecular cyclization of the intermediate isocyanates with the hydroxy group of the pyrazole side chain. In the case of a secondary alcohol (R = Me), the six-membered pyrazolo-oxazine derivatives (105) are also formed (Equation (4)) <82JCR(S)20>. 

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