From dipivaloylketene to tetraoxaadamantanes

• Gert Kollenz and
• Curt Wentrup

Beilstein J. Org. Chem. 2018, 14, 1–10, doi:10.3762/bjoc.14.1

• of the bisdioxines becomes severely hindered in cyclic derivatives, so that the 38-membered ring compound 32 requires microwave heating at 170 °C to form tetraoxaadamantane 33, and the catenated compound 36 and calix[6]arene derivative 37 did not form tetraoxaadamantanes. The reaction mechanisms of

• bisdioxine and tetraoxaadamantane formation are discussed. Keywords: bisdioxines; dipivaloylketene; tetraoxaadamantanes; transannular cyclization; Introduction The tetraoxaadamantane ring system is relatively unknown and no functional group derivatives had been reported prior to our work. The first methyl

• decarboxylated tetraoxaadamantane can be obtained. It is noteworthy that, when a free carboxylic acid moiety is present in the bisdioxine, it is invariably lost during the tetraoxaadamantane formation. The decarboxylation is likely to take place in the acrylic acid moieties in the trioxanonadienes during the

Synthesis of functionalized macrocyclic derivatives of trioxabicyclo[3.3.0]nonadiene

• Sabine Leber,
• Gert Kollenz and
• Curt Wentrup

Beilstein J. Org. Chem. 2012, 8, 738–743, doi:10.3762/bjoc.8.83

• functionalized with nitroaryl and arylamino groups were synthesized from the bisdioxine diacid dichloride 1,3,5,7-tetra-tert-butyl-2,6,9-trioxabicyclo[3.3.1]nona-3,7-diene-4,8-dicarbonyl dichloride (3). Keywords: bisdioxine; macrocyclic amines; macrocyclic nitro compounds; tetraoxaadamantane; Introduction The

• the mono-tetraoxaadamantane derivative 14 (Scheme 4), but all attempts to convert the second bisdioxine unit were fruitless, presumably due to steric hindrance. Force-field calculations [16] indicate that the internal cavity is much smaller in 11 than in 8, and in fact it was not possible to prepare a

• tetraoxaadamantane derivative of nitro compound 11. There is a significant cavity in 8, obviously large enough to form one tetraoxaadamantane derivative, but this reduces the available space, with the consequence that the attack by a water molecule on the second bisdioxine unit from the concave inside of the