17324-04-8Relevant articles and documents
Synthesis and structural analysis of oligo(naphthalene-2,3-diyl)s
Motomura, Takahisa,Nakamura, Hideko,Suginome, Michinori,Murakami, Masahiro,Ito, Yoshihiko
, p. 142 - 146 (2005)
Oligo(naphthalene-2,3-diyl)s are synthesized by the palladium-catalyzed cross-coupling reactions of 2-naphthyl-zinc compounds with 2-bromonaphthalene derivatives. An NMR analysis together with an X-ray diffraction study supports the conjecture that the helical secondary structure is a common feature of the assemblies in which naphthalene-like aromatic units are linked together between the β-positions in series.
C-H Nickelation of Naphthyl Phosphinites: Electronic and Steric Limitations, Regioselectivity, and Tandem C-P Functionalization
Mangin, Lo?c P.,Zargarian, Davit
, p. 4687 - 4700 (2019)
This report describes the results of a study on the C-H nickelation of phosphinites derived from variously substituted 1- and 2-naphthols, as well as the C-P functionalization of the Ni-naphthyl moiety arising from the C-H cyclonickelation. Refluxing 4-X-1-naphthyl phosphinites (X = H, 1a; MeO, 1b; Cl, 1c) with {(i-PrCN)NiBr2}n and Et3N in acetonitrile gave the nickelacyclic complexes {(κP,κC-4-X-1-OP(i-Pr)2-naphth-2-yl)Ni(μ-Br)}2, 2a-c, resulting from cyclonickelation at the C2-H, whereas cyclonickelation of the 2-naphthyl phosphinite analogue 1e under the same conditions occurred at C3-H. Placing a Me substituent at the C3 position of a 2-naphthyl phosphinite (1f) led to a very sluggish nickelation at the C1-H position, whereas 2-ethyl-1-naphthyl phosphinite (1d) failed to nickelate at C8-H. H/D scrambling tests conducted on the deuterated analogue of 1a (1a-d7) confirmed that nickelation occurs exclusively at C2. Similar tests conducted on deuterated analogues of alkyl-substituted 1- and 2-naphthyl phosphinites showed that no nickelation takes place at Csp3-H sites of the alkyl substituents. In contrast, very facile C-H nickelation was observed with 2-allyl-1-naphthyl phosphinite 1g to give a product featuring a π-allyl-Ni moiety. A series of tests have shown that the nickelation of substrates 1a, 1e, and 1f can be accelerated dramatically at 120-160 °C. On the other hand, conducting the high temperature reaction of 1a in the absence of Et3N resulted in an unanticipated and interesting C-P functionalization of the C2-H site, thus generating a i-Pr2P-substituted bidentate phosphine-phosphinite. A similar tandem C-H nickelation/C-P(O) functionalization was also observed at the C8-H position of substrate 1d. The mechanisms of these functionalization reactions have been probed and outlined.
Synthesis of Phenacene-Helicene Hybrids by Directed Remote Metalation
Kancherla, Sindhu,J?rgensen, K?re B.
supporting information, p. 11140 - 11153 (2020/11/20)
Polycyclic aromatic hydrocarbons (PAHs) with six and seven rings were synthesized via directed metalation and cross-coupling of chrysenyl N,N-diethyl carboxamides with o-tolyl and methylnaphthalenyl derivatives. In the presence of competing ortho sites, the site selectivity in iodination of chrysenyl amides by directed ortho metalation (DoM) was influenced by the lithium base. The catalyst ligand bite angle was presumably important in the cross-coupling of sterically hindered bulky PAHs. Subsequent directed remote metalation of biaryls under standard conditions and at elevated temperatures afforded various fused six- and seven-ring PAHs, all in good yields and with fluorescent properties.
De Novo Synthesis of Phenols and Naphthols through Oxidative Cycloaromatization of Dienynes
Rong, Ming-Guang,Qin, Tian-Zhu,Liu, Xin-Rui,Wang, Hong-Fa,Zi, Weiwei
supporting information, p. 6289 - 6293 (2018/10/09)
In this work, a rhodium-catalyzed oxidative cycloaromatization of dienynes, which provides a highly straightforward and efficient way to access polysubstituted naphthols and phenols under mild conditions, is described. Challenged electron-withdrawing groups are well tolerated in this protocol, and late-stage phenyl ring formation is demonstrated.
The ketene-surrogate coupling: Catalytic conversion of aryl iodides into aryl ketenes through ynol ethers
Zhang, Wenhan,Ready, Joseph M.
supporting information, p. 8980 - 8984 (2014/11/07)
tert-Butoxyacetylene is shown to undergo Sonogashira coupling with aryl iodides to yield aryl-substituted tert-butyl ynol ethers. These intermediates participate in a [1,5]-hydride shift, which results in the extrusion of isobutylene and the generation of aryl ketenes. The ketenes are trapped in situ with multiple nucleophiles or undergo electrocyclic ring closure to yield hydroxynaphthalenes and quinolines.
Acid-catalyzed dehydration of naphthalene-cis-1,2-dihydrodiols: Origin of impaired resonance effect of 3-substituents
Kudavalli, Jaya Satyanarayana,Boyd, Derek R.,Sharma, Narain D.,More O'Ferrall, Rory A.
supporting information; experimental part, p. 9338 - 9343 (2012/01/03)
Acid-catalyzed dehydrations of substituted naphthalene-cis-1,2-dihydrodiols occur with loss of the 1- or 2-OH group to form 2- and 1-naphthols, respectively. Effects of substituents MeO, Me, H, F, Br, I, and CN at 3-, 6-, and 7-positions of the naphthalene ring are consistent with rate-determining formation of β-hydroxynaphthalenium ion (carbocation) intermediates. For reaction of the 1-hydroxyl group the 3-substituents are correlated by the Yukawa-Tsuno relationship with ρ = -4.7 and r = 0.25 or by σp constants with ρ = -4.25; for reaction of the 2-hydroxyl group the 3-substituents are correlated by σm constants with ρ = -8.1. The correlations for the 1-hydroxyl imply a surprisingly weak resonance interaction of +M substituents (MeO, Me) with a carbocation reaction center but are consistent with the corresponding correlation for acid-catalyzed dehydration of 3-substituted benzene-cis-1,2-dihydrodiols for which ρ = -6.9 and r = 0.43. Substituents at the 6- and 7-positions of the naphthalene rings by contrast are correlated by σ+ with ρ = -3.2 for reaction of the 1-hydroxyl group and ρ = -2.7 for reaction of the 2-hydroxyl group. The unimpaired resonance implied by these substituent effects appears to be inconsistent with a previous explanation of the weak resonance of the 3-substituents in terms of imbalance of charge development and/or nonplanarity of the benzenium ring in the transition state. An alternative possibility is that the adjacent hydroxyl group interferes sterically with conjugation of +M substituents. "Hyperaromaticity" of the arenium ion intermediates does not appear to be a factor influencing this behavior.
Annulation Reactions Leading to Naphtalene Derivatives. New Syntheses of Natural 1,2- and 1,4-Naphthoquinones
Ghera, Eugene,Ben-David, Yoshua
, p. 3355 - 3359 (2007/10/02)
1-(Phenylsulfonyl)-2-oxo-3-(methoxycarbonyl)-1,2,3,4-tetrahydronaphthalene derivatives with various C-3 substituents were effectively prepared by a one-step cyclization involving 1--2-(bromomethyl)benzene derivatives and monosubstituted malonic esters.A high yield one-step decarboxylation-desulfonylation of the above products by lithium iodide led to C-3-substituted 2-naphthalenols 7a-g whereas prior C-1 alkylation of the cyclization products provided 1,3-dialkylated 2-naphthalenols 6s,b.Oxidations of compounds 7 to o-naphthoquinones 8a-f further oxidations of the above products to substituted 2-hydroxy-1,4-naphthoquinones provided a new pathway to naturally occuring naphthoquinones like phthiocol (9), droserone methyl ether (10), and lapachol (15).
