Diverging Pathways to Topologically Complex Polycyclic Bis-acetals and Their Ring System Interchange
摘要:
Carbinol-tethered octalin-diols (1), which differ only by the C11 configuration at the angular position, were transformed selectively to three types of structurally unrelated original scaffolds such as unsymmetrical octahydroanthracenes (5/7), furofuranes (6), or spirans (8/9) via a two-step protocol. The 11S* configuration ensures a C13-C4 Friedel Crafts type C C bonding (through an unprecedented oxidative cleavage-triggered domino process) while the 11 R* configuration allows for a C13-C2 Marson-type Friedel Crafts C-C bonding (through a nucleophilic acetal opening).
Modular Construction of Topologically Complex Polycyclic Acetals by Tether-Controlled Domino Reactions
作者:Rafael R. Castillo、Valentina Abet、Maurizio Aquino、Zoila Gandara、Pascal Retailleau、Siméon Arseniyadis
DOI:10.1002/ejoc.201201481
日期:2013.4
Leadtetraacetate mediated oxidative cleavage of octalin-diols (1 and 1′), tethered by variously substituted arenes placed at the angular position (C11), show switchable regioselectivity effects. A highly selective set of regiochemical outcomes can be achieved, producing a range of polycyclic acetals through competing domino paths (A–E). The modular complexity inherent in the type-1 domino precursors