Jump to main content
Jump to site search

Issue 0, 1982
Previous Article Next Article

[4.2]- and [4.3]-Metacyclophanes

Abstract

[4.2]Metacyclophanes may conveniently be prepared via carbene insertion into appropriately protected [2.2]-and/or [3.2]-metacyclophanediones. Thus, starting from [2.2]-metacyclophane-1,10-dione propylene thioacetal (1)[4.2]metacyclophane (6) was obtained (28%, three steps). For the synthesis of [4.3]metacyclophanes, [4.2] metacyclophane-2,12-dione (5) served as a key compound. Regioselective carbene insertion into (5) yielded [4.3]metacyclophane-2,13-dione (7) which was transformed into [4.3]metacyclophane (8)[7% starting from (1)]. The ring inversion barriers of (6)(60 kJ mol–1, 308 K) and (8)(<38 kJ mol–1,138 K) were estimated by 1H n.m.r. spectroscopy.

Back to tab navigation

Article type: Paper
DOI: 10.1039/P19820002369
Citation: J. Chem. Soc., Perkin Trans. 1, 1982,0, 2369-2372
  •   Request permissions

    [4.2]- and [4.3]-Metacyclophanes

    D. Krois and H. Lehner, J. Chem. Soc., Perkin Trans. 1, 1982, 0, 2369
    DOI: 10.1039/P19820002369

Search articles by author

Spotlight

Advertisements