Sumio Ishikawa

A convenient, one-pot azulene synthesis from 2H-cyclohepta[b]furan-2-ones with vinyl ether and its analogues. III, Orthoesters as a reagent

2-Alkoxy and 2,4-dialkoxyazulene derivatives were synthesized in one-pot and in good yields by the reaction of 2H-cyclohepta[b]furan-2-ones with orthoesters on heating either neat or in an aprotic solvent at 160-190 o C

A convenient, one-pot azulene synthesis from cyclohepta[b]furan-2-ones and vinyl ether and its analogues. II: Acetals as reagent

Title synthesis by the reaction of cyclohepta[b]-furan-2-ones with acetals of several aldehydes and ketones on heating at 160-190 o C in neat or aprotic solvent

A convenient, one-pot synthesis of azulenes having versatile functional groups by the reaction of 2H-cyclohepta[b]furan-2-ones with furan derivatives

2-Acylmethyl- and 2-methoxycarbonylmethylazulene derivatives having versatile functional groups in the side chain, are synthesized in one-pot by the reaction of 2H-cyclohepta [b] furan-2-ones with furans on heating at 160-190 ° C in aprotic solvent

A convenient, one-pot synthesis of tropocoronands and tropopodands by use of the heterocycle-exchange reaction of benzo[b]cyclohepta[e][1,4]oxazine

Treatment of benzo[b]cyclohepta[e][1,4]oxazine with 1.2 equiv. of α,ω-diaminoalkanes (n=4-12) in ethanol at 80°C gave tropocoronands (n=4-12) in one step in high yields, while the reaction of 5 with an excess of 2 afforded tropopodands (n=4-6). The reactions of 5 with 2 (n=2,3) yielded bicyclic pyrazino or diazepino compounds in high yields. Coronands [14 (instead of 4a) and 4b (n=3)] were, however, obtained by the reaction of 5 with N-acetyldiaminoalkanes. The reaction of 5 with α,ω-amino alcohol afforded the corresponding podands