1624-33-5Relevant academic research and scientific papers
C-C Bond-Forming and Bond-Breaking Processes from the Reaction of Diesters with Me3SnLi. Synthesis of Complex Bridged Polycycles and Dialkyl Aromatic Compounds
Martínez-García, Lucas,Lobato, Rubén,Prado, Gustavo,Monje, Pablo,Sardina, F. Javier,Paleo, M. Rita
, p. 1887 - 1897 (2019)
1,2-Aromatic diesters can be transformed into strained bridged polycyclic structures by a two-step procedure consisting of an initial reductive alkylation promoted by alkaline metals, followed by a reaction of the resulting unsaturated diesters with Me3SnLi. We propose that a stanna-Brook rearrangement plays a fundamental role in the formation of the polycyclic organotin acetals obtained. These unusual compounds could be further functionalized by tin-lithium exchange followed by alkylation of the newly formed tertiary carbanion. Alternatively, dialkylated aromatic hydrocarbons have been prepared via a decarbonilation reaction promoted by Me3SnLi. 1,4-Aromatic diesters were reductively dialkylated and then transformed into norbornadienone derivatives by reaction with Me3SnLi. Several stable dibenzonorbornadienones 41 have been prepared in just two steps starting from anthracene 38. The corresponding naphthalene analogues gave 1,4-dialkylnaphthalenes. The synthetic protocols described provide access to structures that are not easily obtained through existing synthetic methodologies.
N.M.R. Spectra and Conformations of 9,10-Dihydroanthracenes
Ahmad, Naseer-ud-din,Cloke, Christopher,Hatton, Ian K.,Lewis, Norman J.,MacMillan, Jake
, p. 1849 - 1858 (2007/10/02)
The preparation of a series of substituted 9,10-dihydroanthracenes is described and their proton n.m.r. spectra are dicussed.It is suggested that the trans-isomers of 9,10-dialkyl-9,10-dihydroanthracenes, substituted in the 9,10- or peri-positions adopt a polar ring conformation with the 9,10-dialkyl substituents placed over the ring.It is further suggested that the highfield signal of the β-protons of the 9,10-dialkyl substituents is due to partly to the magnetic anisotropy of the aromatic rings, and partly to the magnetic anisotropy of the carbon-carbon bonds from the alkyl groups to the 9- and 10-positions in the central ring.
