14472-44-7Relevant academic research and scientific papers
Alcohol Etherification via Alkoxy Radicals Generated by Visible-Light Photoredox Catalysis
Rivero, Alexandra R.,Fodran, Peter,Ondrejková, Alica,Wallentin, Carl-Johan
, p. 8436 - 8440 (2020/11/03)
A mechanistically divergent method is described that, employing a commercially available hypervalent iodine(III) reagent, generates alkoxy radicals from 1°, 2°, and 3° alcohols and allows their use in the functionalization of C(sp3)-H and C(sp2)-H bonds. This visible-light photoredox catalysis produces alkyl ethers via 1,5/6-hydrogen atom transfer or aryl ethers via 1,5-addition. This mild methodology provides a practical strategy for the synthesis of acetals, orthoesters, tetrahydrofurans, and chromanes.
Synthesis of chromans via [3 + 3] cyclocoupling of phenols with allylic alcohols using a Mo/o-chloranil catalyst system
Yamamoto, Yoshihiko,Itonaga, Kouhei
scheme or table, p. 717 - 720 (2009/08/19)
(Chemical Equation Presented) The combination of a molybdenum complex (CpMoCl(CO)3 or [CpMo(CO)3]2) and o-chloranil was used as a catalyst in the [3 + 3] cyclocoupling of phenols and allylic alcohols under microwave heating conditions. Substituted chromans were selectively obtained in moderate to good isolated yields.
Claisen Rearrangement of Prenyl Ethers of Isomeric Acetylnaphthols and Bisprenyl Ethers of 4,6- and 2,4-Diacetylresorcinols
Anjaneyulu, Ammanamanchi S. R.,Isaa, Balagopala M.
, p. 2089 - 2094 (2007/10/02)
Claisen rearrangements of the 3-methylbut-2-enyl(prenyl)ethers 3 and 9 of 2-acetyl-1-hydroxy- and 1-acetyl-2-hydroxynaphthalenes 1 and 2 and the bis(3-methylbut-2-enyl)ethers 12 and 18 of 2,4- and 4,6-diacetylresorcinols 11 and 17 have been studied under a variety of thermal and catalytic conditions. 2-Acetyl-4-(3-methylbut-2-enyl)naphthalene-1-ol 4 was the sole product on rearrangement of compound 3, in DMA or neat.Under catalytic conditions 3,4-dihydro-2,2-dimethyl-2H-naphthopyran 7 was obtained in poor yield.An isomeric pyran, 1,2-dihydro-3,3-dimethyl-3H-naphthopyran 10 (25-43percent) was obtained under both thermal and catalytic conditions from 9.The rearrangement of 12 under thermal conditions (DMA and neat) furnished 3-acetyl-2,4-dihydroxy-5-(3-methylbut-2-enyl)acetophenone 13 and 3,8-diisopropylbenzodifuran 14.Pd'' mediated rearrangement of 12 gave only the partially deprenylated ether, 3-acetyl-4-hydroxy-2-(3-methylbut-2-enyloxy)acetophenone 15 (29percent).While the isomeric ether 18 gave the monoprenyl ether, 5-acetyl-4-hydroxy-2-(3-methylbut-2-enyloxy)acetophenone 19 in quantitative yield (95percent).The rearrangment products were characterised and their formation rationalised in terms of allowed sigmatropic shifts( prenyl and H) followed by loss of prenyl or acetyl groups.The reactions of prenyl ethers are both comparable to those of the corresponding allyl ethers and consistent with the greater fixed double-bond character of the naphthalene system compared to that of benzene.Prenyl derivatives of benzene and naphthalene containing ortho - hydroxyacetophenone units were formed which have potential in synthesis.
REGIOSPECIFIC CATALYTIC ALKENYLATION OF AROMATIC SUBSTRATES WITH COORDINATED DIENES: REACTIONS ON NAPHTHALENE DERIVATIVES. PRELIMINARY RESULTS ON HETEROAROMATIC SUBSTRATES
Renzi, Augusto De,Lombardi, Angelina,Panunzi, Achille,Saporito, Antonio
, p. 657 - 660 (2007/10/02)
α- and β-naphthol undergo regiospecific alkenylation by 1,1-dimethylallene (DMA) at the OH-adjacent β- and α-positions, respectively, when allowed to react with DMA-Pt(II) complex.A catalytic process can be achieved with conversions higher than 90percent.A Pd(II) complex as promotor and isoprene as alkenylating diene can also be used.Similar results were obtained with N-acetyl-β-naphthylamine.Preliminary results indicated that nitrogen-containing heteroaromatic substrates can afford N-, O- or C-isopentenyl derivatives depending on the particular features of the organic ring.
