Functionalization of naphthalene: a novel synthetic route to brominated naphthoquinones

Abstract

An efficient procedure is described for synthesis of 2,5,8-tribromonaphthoquinone (12) from naphthalene in four reaction steps. Silver-promoted solvolysis of hexabromide 3 produces the specific diastereostereoisomer 10. Dehydrobromination of 10 using sodium methoxide gives tribromodihydronaphthalene-1,4-diol 11 in high yield. PCC oxidation of either 10 or 11 results in the formation of 2,5,8-tribromonaphthalene-1,4-dione (12).

Novel O‐propyl, S‐propyl, and N‐propyl substituted 1,4‐naphthoquinones and 1,4‐anthraquinones as potential fingermark development reagents for porous surfaces

“…The 1 H NMR spectra of 10 and 13 showed one additional singlet for the NH hydrogen at δ 5.81 and δ 5.86, respectively Table 7. The 1 H NMR spectra of the aromatic protons of compounds 10 , 11 , and 12 formed an AB system (these protons resonated as a singlet at δ 7.83 in the 1 H NMR spectra of compound 8 ) [22]. The four aromatic protons of compounds 14 and 15 formed an AA'BB’ system while three sets of signals were observed for the aromatic protons of compound 13 Table 7.…”

“…The IR spectra were recorded on a Jasco FT/IR 430 instrument. 2,5,8-tribromo-1,4-naphthoquinone 8 and 2,9,10-tribromo-1,4-anthraquinone 9 were synthesized as described in literature [22,23]. HFE-7100 was purchased from 3 M Novec.…”

Synthesis and Biological Evaluation of Novel 5,8-Dibromo-2-N-substituted-1,4-Naphthoquinone Derivatives as Potential Antimicrobial Agents

“…(1) was synthesized using known procedures [9]. Column chromatography was carried out using Merck 60 (70-230 Mesh) silica.…”

“…Analysis of the 1 H NMR in CDCl 3 showed the formation of the 2a-2g by the presence of signals attributed to the H 3 and NH protons. Furthermore, while the two protons on the aromatic ring in the 2,5,8-tribromonaftalin-1,4-dion (1) appear as a singlet at 7.8 ppm [9], these protons give an AB system after attaching to an electron donor group in position 2 of the compound. 13 C NMR spectra are also in agreement with the proposed structures.…”

Bromination and conversion of tetrahydro-1H-indene to bisoxirane with a new approach: synthesis, structural characterization by spectroscopic and theoretical methods, and biological analysis supported by DFT and docking

“…In some cases, stereoselective epoxide derivatives can be obtained through base-induced dehydrobromination of naphthalene and anthracene in the presence of silver ions [ 12 – 14 ]. Although bisbromoacetate was used as a starting compound for syn- and anti-diepoxides, the efficiency was relatively low (5%–10%) [ 15 ].…”