10.1021/acs.joc.5b00931.s006
Paul F. Thomson
Paul F.
Thomson
Damon Parrish
Damon
Parrish
Padmanava Pradhan
Padmanava
Pradhan
Mahesh K. Lakshman
Mahesh K.
Lakshman
Modular, Metal-Catalyzed
Cycloisomerization Approach
to Angularly Fused Polycyclic Aromatic Hydrocarbons and Their Oxidized
Derivatives
American Chemical Society
2015
benzo
THF
PtCl 2
BBr 3
NaBH 4
Angularly Fused Polycyclic Aromatic Hydrocarbons
series 1 diol epoxides
2O
HO
oxygen atmosphere
acid
hydrocarbon
DDQ
ethynylphenyl
isomeric series 2 diol epoxides
Cycloisomerization
IRA
PDC
BcPh derivatives
dihydrodiol
2015-08-07 00:00:00
Dataset
https://acs.figshare.com/articles/dataset/Modular_Metal_Catalyzed_Cycloisomerization_Approach_to_Angularly_Fused_Polycyclic_Aromatic_Hydrocarbons_and_Their_Oxidized_Derivatives/2142778
Palladium-catalyzed cross-coupling
reactions of 2-bromobenzaldehyde
and 6-bromo-2,3-dimethoxybenzaldehyde with 4-methyl-1-naphthaleneboronic
acid and acenaphthene-5-boronic acid gave corresponding <i>o</i>-naphthyl benzaldehydes. Corey–Fuchs olefination followed
by reaction with <i>n</i>-BuLi led to various 1-(2-ethynylphenyl)naphthalenes.
Cycloisomerization of individual 1-(2-ethynylphenyl)naphthalenes to
various benzo[<i>c</i>]phenanthrene (B<i>c</i>Ph) analogues was accomplished smoothly with catalytic PtCl<sub>2</sub> in PhMe. In the case of 4,5-dihydrobenzo[<i>l</i>]acephenanthrylene,
oxidation with DDQ gave benzo[<i>l</i>]acephenanthrylene.
The dimethoxy-substituted benzo[<i>c</i>]phenanthrenes were
demethylated with BBr<sub>3</sub> and oxidized to the <i>o</i>-quinones with PDC. Reduction of these quinones with NaBH<sub>4</sub> in THF/EtOH in an oxygen atmosphere gave the respective dihydrodiols.
Exposure of the dihydrodiols to <i>N</i>-bromoacetamide
in THF-H<sub>2</sub>O led to bromohydrins that were cyclized with
Amberlite IRA 400 HO<sup>–</sup> to yield the series 1 diol
epoxides. Epoxidation of the dihydrodiols with <i>m</i>CPBA
gave the isomeric series 2 diol epoxides. All of the hydrocarbons
as well as the methoxy-substituted ones were crystallized and analyzed
by X-ray crystallography, and these data are compared to other previously
studied B<i>c</i>Ph derivatives. The methodology described
is highly modular and can be utilized for the synthesis of a wide
variety of angularly fused polycyclic aromatic hydrocarbons and their
putative metabolites and/or other derivatives.