74794-06-2Relevant academic research and scientific papers
Allylation of quinones bu allylic indium reagents
Araki, Shuki,Katsumura, Nobuhito,Butsugan, Yasuo
, p. 7 - 24 (2007/10/02)
Allylation of a variety of quinones by allylic indium sesquihalides was studied.Reactions of unsubstituted p-benzoquinone with allylindium, prenylindium, and geranylindium reagents gave, after oxidation with silver oxide, the corresponding allylated quinones in good yields.These reactions appear to proceed via 1,2-addition of the allylic indium reagents at the γ-carbon followed by sigmatropic rearrangement.Substituted quinones reacted with allylindium reagent giving excellent yields of allylquinols, whereas with prenylindium and geranylindium reagents, trisubstituted quinones gave diprenylcyclohexene-1,4-diones and 2,3-disubstituted quinones gave mixtures of prnylhydroquinones and diprenylcyclohexene-1,4-diones.In the prenylation of haloquinones, 1,2-addition, sigmatropic rearrangement, and elimination of indium(III) halide occurred in sequence yielding prenylquinones. 2-Hydroxy- and 2-methoxy-1,4-naphthoquinones gave α-addition products with prenylindium and cinnamylindium reagents.
Allylation of Quinones with Allyltin Reagents
Naruta, Yoshinori
, p. 3774 - 3783 (2007/10/02)
Lewis acid (BF3) catalyzed allylation of quinones with allyl- (2a), 2-methyl-2-propenyl- (2b), trans-2-butenyl- (2c,d), 3-methyl-2-butenyl- (2e,f), and trans-cinnamyltrialkyltin (2g) gives the corresponding allylhydroquinones with high regioselectivity.Vitamin K2(5) (7) and coenzyme Q1 (9) were prepared in yields of 78 and 75percent, respectively.These reactions appear to proceed through allylquinol intermediates which undergo rearrangement under the influence of BF3.The success of this synthesis of vitamin K2(5) and coenzyme Q1 depends on the fact that the reaction of 3-methyl-2-butenyltin with quinones occurs at the α carbon of the allylic system.
