569-42-6Relevant academic research and scientific papers
First report of a permanent open form of a naphthopyran
Martins, Cristina I.,Coelho, Paulo J.,Carvalho, Luis M.,Oliveira-Campos, Ana M.F.
, p. 2203 - 2205 (2002)
The synthesis of a permanent open form of a naphthopyran is described for the first time. The open form of the 10-hydroxy-2H-naphtho[1,2-b]pyran, obtained by reaction of 1,8-dihydroxy-naphthalene with 1,1-diphenylprop-2-yn-1-ol under acid catalysis, is stable due to the establishment of an intramolecular hydrogen bond.
Iridium-Catalyzed, Silyl-Directed, peri-Borylation of C?H Bonds in Fused Polycyclic Arenes and Heteroarenes
Su, Bo,Hartwig, John F.
, p. 10163 - 10167 (2018)
peri-Disubstituted naphthalenes exhibit interesting physical properties and unique chemical reactivity, due to the parallel arrangement of the bonds to the two peri-disposed substituents. Regioselective installation of a functional group at the position peri to 1-substituted naphthalenes is challenging due to the steric interaction between the existing substituent and the position at which the second one would be installed. We report an iridium-catalyzed borylation of the C?H bond peri to a silyl group in naphthalenes and analogous polyaromatic hydrocarbons. The reaction occurs under mild conditions with wide functional group tolerance. The silyl group and the boryl group in the resulting products are precursors to a range of functional groups bound to the naphthalene ring through C?C, C?O, C?N, C?Br and C?Cl bonds.
Hydrosilyl Group-directed Iridium-catalyzed peri-Selective CH Borylation of Ring-fused (Hetero)Arenes
Sumida, Yuto,Harada, Ryu,Sumida, Tomoe,Hashizume, Daisuke,Hosoya, Takamitsu
, p. 1251 - 1254 (2018)
The iridium-catalyzed direct CH borylation of ring-fused (hetero)arenes afforded borylated products in a peri-selective manner, directed by a proximal hydrosilyl group. Further selective transformations of the boryl and silyl groups enabled the synthesis of various multisubstituted (hetero)arenes, such as 1,8-disubstituted naphthalenes and 3,4-diarylindole.
Boronic, diboronic and boric acid esters of 1,8-naphthalenediol-synthesis, structure and formation of boronium salts
Krempner, Clemens,Manankandayalage, Chamila P.,Unruh, Daniel K.
supporting information, p. 4834 - 4842 (2020/04/27)
The 1,8-naphthalenediolate [1,8-O2C10H8] supported boronic and boric acid esters of general formula X-B(1,8-O2C10H8), where X = C6H5 (1a), C6F5 (2a), 3,4,5-F3-C6H2 (3a), 2,4,6-F3-C6H2 (4a), 2,6-F2-C6H3 (5a), 2,6-Cl2-C6H3 (6a), 2,4,6-Me3-C6H2 (7a), 2,6-(MeO)3-C6H3 (8a), Bun (9a), MeO (10a), OH (11a) and Cl (13a), were synthesized, NMR spectroscopically characterized, and the solid-state structures of 1a-5a, 8a and 10a determined by X-ray crystallography. The acceptor numbers of 1a-7a and 13a were determined and found to be similar to their catecholate analogues, R-Bcat, indicating similar Lewis acidities of these two classes of boronic acid esters. The reaction of B2(NMe2)4 with 1,8-naphthalenediol, followed by addition of HCl furnished the diboronic acid ester B2(1,8-O2C10H8)4 (16a) in ca. 70% yield. Cl-B(1,8-O2C10H8) (13a) was shown to react with OPEt3, DMAP, 1,10-phenanthroline and 2,2′-bipyridine, resp., to give the boronium salts [(Et3PO)2B(1,8-O2C10H8)]Cl (18a), [(DMAP)2B(1,8-O2C10H8)]Cl (22a), [(2,2′-bipyridine)B(1,8-O2C10H8)]Cl (23a) and [(1,10-phenanthroline)B(1,8-O2C10H8)]Cl (24a), which were characterized by NMR spectroscopy and X-ray crystallography.
Synthesis of naphthalenophane-type macrocyclic compounds using Mn(III)-based dihydrofuran-clipping reaction
Matsumoto, Chiaki,Yasutake, Ken-ji,Nishino, Hiroshi
supporting information, p. 6963 - 6971 (2016/10/14)
The Mn(III)-based oxidation of 2,7-, 1,8-, and 1,5-disubstituted naphthalenes bearing both the 1,4-dioxa-7,7-diphenylhep-6-enyl and 1,4-dioxa-5,7-dioxooctyl groups gave new [12]naphthalenophanes along with the corresponding diploids via assembly of the dihydrofuran ring. A similar reaction of the 2,6-disubstituted naphthalene having the same substituents did not produce the naphthalenophane, but the diploid, [12,12](2,6)naphthalenophane, was obtained in a small amount. The 2,6-disubstituted naphthalene tethered to the 1,4,7-trioxa-10,10-diphenyldec-9-enyl and 1,4,7-trioxa-8,10-dioxoundecyl groups also underwent the dihydrofuran-clipping reaction to afford a trace amount of the desired [18](2,6)naphthalenophane. The reaction details and the structure determination of the products are described.
Influence of Backbone Substituents on the Ethylene (Co)polymerization Properties of α-diimine Pd(II) and Ni(II) Catalysts
Zou, Wenping,Chen, Changle
, p. 1794 - 1801 (2016/07/06)
A series of α-diimine ligands with different substituents on the acenaphthyl backbone were synthesized and characterized. The corresponding Ni(II) and Pd(II) complexes were prepared and used in ethylene polymerization and copolymerization with methyl acrylate. In ethylene polymerization, these Ni(II) complexes showed activities of up to 1.6 × 107 g/((mol of Ni) h), generating polyethylene with a molecular weight (Mn) of up to 4.2 × 105. Interestingly, these Ni(II) complexes behave very similarly in ethylene polymerization except for the complex with two methoxy substituents on the ortho position of the acenaphthyl backbone, in which case about 3 times higher polyethylene molecular weight and much lower branching density were observed. The ligand substituent effect is much more dramatic for the Pd(II) complexes. In ethylene polymerization, activities of up to 1.7 × 105 g/((mol of Pd) h) and a polyethylene molecular weight (Mn) of up to 4.7 × 104 could be obtained. The Pd(II) complex with two methoxy substituents on the ortho position of the acenaphthyl backbone demonstrated much higher activity and generated polyethylene with about 3 times higher molecular weight than that for the classic Pd(II) complex. A similar trend was maintained in ethylene-methyl acrylate copolymerization.
Total synthesis of the natural product benzo[j]fluoranthene-4,9-diol: An approach to the synthesis of oxygenated benzo[j]fluoranthenes
Lahore, Santosh,Narkhede, Umesh,Merlini, Lucio,Dallavalle, Sabrina
, p. 10860 - 10866 (2013/11/19)
A synthetic sequence to the benzo[j]fluoranthene nucleus is described. Crucial steps of the procedure include a Suzuki coupling between appropriately substituted 2-bromo-acenaphthylene-1-carbaldehydes and 2-formylbenzeneboronates followed by McMurry ring closure. The synthesis represents a new approach to the benzo[j]fluoranthene ring system and specifically provides a method for the rapid preparation of differently substituted derivatives. Following this strategy, the first total synthesis of the recently isolated natural product benzo[j]fluoranthene-4,9-diol was carried out.
Neutral Bimetallic Transition Metal Phenoxyiminato Catalysts and Related Polymerization Methods
-
Page/Page column 10, (2013/03/26)
A catalyst composition comprising a neutral bimetallic diphenoxydiiminate complex of group 10 metals or Ni, Pd or Pt is disclosed. The compositions can be used for the preparation of homo- and co-polymers of olefinic monomer compounds.
SYNTHESIS OF THE POTENT IMMUNOSUPPRESSANT AGENTS DALESCONOL A AND B
-
Page/Page column 7; 65-66, (2011/09/19)
This invention relates to compounds having the structure: wherein bonds α, β, γ, δ, ω, η, χ, ε, κ, and μ are each present or absent, and R1-R18 are various substituents described herein.
A concise approach to the dalesconol skeleton
Fan, Yukai,Feng, Pengju,Liu, Mao,Pan, Hongjie,Shi, Yian
supporting information; experimental part, p. 4494 - 4497 (2011/10/11)
A rapid approach to the skeleton of dalesconol A and B, unprecedented immunosuppressants, has been achieved through a convergent strategy featuring a carbocation-mediated dearomatization-cyclization and a following one-pot consecutive operation.
