Synthesis of [5.5.5.5]fenestranes by pd-catalyzed carbonylation-cyclisation

✍ Scribed by Reinhart Keese; Regine Guidetti-Grept; Beat Herzog

• Publisher: Elsevier Science
• Year: 1992
• Tongue: French
• Weight: 243 KB
• Volume: 33
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)91897-5

✦ Synopsis

Pd-catalyzed reaction of 3-acetoxy-8-butenyl-@ and 8-but-3-inyl-bicyclo[3.3.0]oct-1 -ene (11) with CO in CH3COOf-I lead via double annulation to alLcis[5555]fenestranes. Common feature of a variety of recently developed methods for synthesis of diquinanes from openchain compounds is the transition metal catalyzed cyclisation -carbonylation -of 1,6-ene-ynes rasp. 1,6-di-enes [l]. Thus, bicyclic enones are obtained by the intramolecular Pauson-Khand-reaction [2], preferably in the presence of a co-reagent [3] and by the Negishi-method of bicyclization promoted by zirconocene derivatives with the subsequent reaction of the zirconacycles with CO [4]. Bicyclic enones and ketones are also prepared by treatment of 1,6-ene-ynes resp. 1,6-di-enes with Ni(O)-or Pd(O)-complexes and CO under mild conditions [5]. The latter methodology developed and explored by Oppolzer, has the following main features (Scheme 1, Y = NTs, C(COOCH3)2, C(CH3)2). COOR X 1 r Y Y RODC Depending on the metal and its ligands, cis-or trans-substituted cyclopentanes resp. cis-bicyclo[3,3,0]octan3-ones 3 may be obtained from 1,6-dienes, whereas 1,6-ene-ynes give cyclopentylidene derivatives or bicyclo[3.3.3]oct-1 -en-3-ones. Common structural feature of the 1,6-di-enes resp. 1,6-ene-ynes is a disubstituted double-bond with E-configuration and a leaving group (X = I, i 207