Cyclophanes. 32. Bridging of the [2.2]paracyclophane nucleus by a phenanthrene unit

Transannular Hydride Migration in Pseudo‐Geminally Substituted [2.2]Paracyclophanes: A Vinylogous Pinacol Rearrangement

“…The synthesis of 4,13-bis(phenylhydroxymethyl)[2.2]paracyclophane 7 has been previously reported by us. [9] As in the case of pseudo-geminal bispropargylic alcohols 1a-c, it has always been obtained as a single stereoisomer, the NMR spectra (experimental section) indicating a symmetrical meso-form. 4,13-Bis(α-hydroxyethyl)[2.2]para- cyclophane has been synthesized under similar reaction conditions from 4,13-diformyl[2.2]paracyclophane 6 [10] and methylmagnesium bromide (Scheme 4).…”

A New Way to Generate Functionalized Bridges in [2,2]Cyclophanes

“…This photocyclization step has been carried out by irradiating 3b (10 -3 M in toluene) in the presence of iodine (0.1 equiv) and biacetyl (2.5 equiv) with a TQ 150 high-pressure mercury lamp (Scheme 4). 21,22 The structure of compound 4, which was isolated in 23% yield, has again been unambiguously proven by 2D NMR analysis. 23 After photolysis, the overlapping aromatic signals of the phenyl substituents of 3b were replaced by the characteristic 1 H NMR spectrum of a 9,10-disubstituted phenanthrene (d = 7.…”

The McMurry Coupling and Related Reactions

“…In many cases, as for 85 [114] and 86 [115], these compounds are formed together with the products resulting from successive inter-and intracyclization reactions (Section 6.2.3) [114][115][116][117][118][119]. Transannular coupling reactions have allowed access to the higher orthocyclophane derivative 87 [120,121], the triply-bridged cyclophane 88 [122], as well as the highly distorted cone calix [4] arenes derivatives, including 97, was synthesized for a study of their photoswitchable properties; the coupling reactions yielded both cis-and trans-stilbenes from o-and m-bis(benzaldehyde)s, while only the cis-stilbene was obtained from the p-isomer [133]. Polyepoxyannulenes such as 98 were found to be highly dynamic systems [134][135][136].…”