Synthese und Reaktionen von β‐Campholenverbindungen

Synthesis and Reactions of β-Campholene Compounds In contrast to the well known α-campholenic (B) and fencholenic compounds (C) little is known about β-campholenic derivatives (A) because of their difficult accessibilitiy. β-Campholenic compounds (A) can be obtained: (1) by Baeyer-Villiger oxidation of camphor via lactone 7 and β-dihydrocampholenic lactone (5); (2) by Beckmann fragmentation of camphor oxime via α-(2) and β-campholenic nitril (3) and the lactone 5; and (3) by acid catalysed rearrangement of α-campholenic derivatives (B, 17a, b). The β-analogous brahmanol (14) can be synthesized by the reaction of the β-campholenic bromide (11) with methyl diethyl malonate or by rearrangement of brahmanol.