88920-58-5Relevant academic research and scientific papers
Synthesis and Photochemical Isomerization of 1,2-Di-9-anthrylethanol and 1,2-Di-9-anthrylethanone
Becker, Hans-Dieter,Hansen, Lars,Andersson, Kjell
, p. 2956 - 2961 (1986)
1,2-Di-9-anthrylethanol has been synthesized by Grignard reaction of 9-anthrylmagnesium bromide with 9-anthrylacetaldyhyde which, in turn, was obtained by oxidation of 9-anthrylethanol with 1,1,1-triacetoxy-1,1-dihydro-1,2-benziodoxol-3(1H)-one ("Dess-Martin periodinane").This oxidant also was found to be the reagent of choice for the conversion of dianthrylethanol into 1,2-di-9-anthrylethanone.The photochemical isomerization of dianthrylethanol in benzene solution proceeds with a quantum yield of 0.34 by intramolecular cycloaddition involving the excited singlet state.Remarkably, the course of photochemical isomerization of 1,2-di-9-anthrylethanone is dependent on the substrate concentration, affording mainly intramolecular cyclomers in dilute (0.00001 M) solution but the intramolecular cycloadduct in concentrated (0.01 M) solution.The proposed triplet state pathway for the formation of intramolecular Diels-Alder products from dianthrylethanone is supported by oxygen quenching results and sensitization experiments with biacetyl.The photochemical isomerization of di-9-anthryl ketone and 1,3-di-9-anthrylpropan-1-one gives rise to intramolecular (ψ=0.0003) and (ψ=0.65) cycloadducts, respectively.The differences in quantum yields and modes of cycloaddition are attributed to differences in molecular geometry.
Preparative methodology and pyrolytic behavior of anthrylmonocarbenes: Synthesis and chemistry of 1H-cyclobuta[de]anthracene
Kendall, J. Kirby,Engler, Thomas A.,Shechter, Harold
, p. 4255 - 4266 (2007/10/03)
This study involves (1) the behavior of organolithium reagents (1-6), (2) development of efficient methods for preparing 9(7)- and 1(8)- [methoxy(trimethylsilyl)methyl]anthracenes and their analogues, (3) the intramolecular chemistry of the 9(9)- and 1(10)-anthrylcarbenes generated by pyrolyses of 7 and 8, respectively, and (4) investigation of thermal behavior and bromination of the 1H-cyclobuta[de]anthracene (11) obtained from 9 or 10. α-Methoxy-9-anthrylmethyllithium (1), prepared from 9- (methoxymethyl)anthracene (14) and t-BuLi in TMEDA/Et2O/pentane, reacts at C-10 with D2O, chlorotrimethylsilane, dimethyl sulfate, benzoyl chloride, acetaldehyde, benzaldehyde, and acetone to give, after neutralization, 9,10- dihydro-9-(methoxymethylene)-10-substituted-anthracenes 15 and 21a-f. However, lithiation of 9-(thiomethoxymethyl)anthracene (25) with t- BuLi/TMEDA/Et2O/pentane occurs by an apparent radical-anion displacement process to give 9-anthrylmethyllithium (3), which then reacts with chlorotrimethylsilane to yield 9-(trimethylsilylmethyl)anthracene (28). Similarly, 28 is formed from 25 and from 9- (trimethylsilyloxymethyl)anthracene (29) with lithium and then chlorotrimethylsilane. The electrophiles D2O, dimethyl sulfate, and benzaldehyde react with 3 at its methyl and its C-10 positions. [Methoxy(trimethylsilyl)methyl]arenes 40-42 and 7 are obtained by reactions of their aryllithium and arylmagnesium bromide precursors with bromo(methoxy)methyltrimethylsilane (39). 1-(Methoxymethyl)anthracene (45) is converted conveniently by t-BuLi and chlorotrimethylsilane to 8. Flash- vacuum pyrolyses of 7 and 8 yield 11 preparatively; 11 then thermolyzes to 2H-cyclopenta[jk]fluorene (46). Decomposition of 9-deuterio-10- [methoxy(trimethylsilyl)methyl]anthracene (55) at 650 °C/10-3 mm results in 10(56)- and 1(57)-deuteriocyclobutanthracenes, thus revealing that the 10- deuterio-9-anthrylcarbene inserts to give 56 and also isomerizes extensively before yielding 57. Of note is that 56 isomerizes thermally by C10-D movement to form 2-deuteriocyclopentafluorene 58, 57 rearranges by C10-H movement to yield deuteriocyclopentafluorene 59, and 58 and 59 equilibrate 1,5-sigmatropically. Possible mechanisms for the isomerizations of 56 and 57 are outlined. Further, bromine adds rapidly to 11 to form 9,10-dibromo-9,10- dihydro-1H-cyclobuta[de]anthracene (94), which eliminates HBr on warming to yield 10-bromo-1H-cyclobuta[de]anthracene (95).
GENERATION AND THE AMBIDENT CHARACTER OF 9-ANTHRYLMETHYL CARBANIONS
Engler, T. A.,Shechter, H.
, p. 4645 - 4648 (2007/10/02)
9-Methoxymethylanthracene, 9-trimethylsilylmethylanthracene and 9-thiomethoxymethylanthracene are converted by butyllithium reagents to α-methoxy-9-anthrylmethyl, α-trimethylsilyl-9-anthrylmethyl and 9-anthrylmethyl carbanions, respectively, which react at their C-10 and C-11 positions with appropriate electrophyles.
