Synthesis and application of precursors of hetero-anthracenes

Bickelhaupt, F.; Jongsma, C.; Koe, P. de; Lourens, R.; MAST, N. R.; Mourik, G.L. van; Vermeer, Hans J.; Weustink, R.J.M.

doi:10.1016/0040-4020(76)85198-8

Cited by 33 publications

(16 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Non-halogenated solvents were tested with a standard purple solution of sodium benzophenone ketyl in tetrahydrofuran in order to confirm effective moisture removal. O -iodotriphenylmethane, 28 H(OEt 2 ) 2 [B(3,5-(CF 3 ) 2 -C 6 H 3 ) 4 ], 42 KC 8 , 43 [(TPB)FeN 2 ][Na(12-crown-4) 2 ], 25 [(SiP i Pr 3 )FeN 2 ][Na(12-crown-4) 2 ] 17 and [(C Si P Ph 3 )FeN 2 ][K(18-crown-6) 2 ] 22 were prepared according to literature procedures. [Decamethylferrocenium][B(3,5-(CF 3 ) 2 -C 6 H 3 ) 4 ] was prepared by treating [ferrocenium][B(3,5-(CF 3 ) 2 -C 6 H 3 ) 4 ] 44 with decamethylferrocene and used without purification.…”

Section: Experimental Methodsmentioning

confidence: 99%

Catalytic Reduction of N₂ to NH₃ by an Fe–N₂ Complex Featuring a C-Atom Anchor

2014

View full text Add to dashboard Cite

While recent spectroscopic studies have established the presence of an interstitial carbon atom at the center of the iron-molybdenum cofactor (FeMoco) of MoFe-nitrogenase, its role is unknown. We have pursued Fe-N2 model chemistry to explore a hypothesis whereby this C-atom (previously denoted as a light X-atom) may provide a flexible trans interaction with an Fe center to expose an Fe-N2 binding site. In this context, we now report on Fe complexes of a new tris(phosphino)alkyl (CPiPr3) ligand featuring an axial carbon donor. It is established that the iron center in this scaffold binds dinitrogen trans to the Calkyl-atom anchor in three distinct and structurally characterized oxidation states. Fe-Calkyl lengthening is observed upon reduction, reflective of significant ionic character in the Fe-Calkyl interaction. The anionic (CPiPr3)FeN2- species can be functionalized by a silyl electrophile to generate (CPiPr3)Fe-N2SiR3. (CPiPr3)FeN2- also functions as a modest catalyst for the reduction of N2 to NH3 when supplied with electrons and protons at -78 °C under 1 atm N2 (4.6 equiv NH3/Fe).

show abstract

Section: Experimental Methodsmentioning

confidence: 99%

Catalytic Reduction of N₂ to NH₃ by an Fe–N₂ Complex Featuring a C-Atom Anchor

2014

View full text Add to dashboard Cite

show abstract

“…[39]. In the synthesis of 9,10-dihydro-9plumbaanthracene derivatives, in which Ε of (1) is a CH 2 group, bis-(o-bromophenyl)methane was used as a starting material rather than the corresponding dichloro compound [4,5]. In the synthesis of 9,10-dihydro-9plumbaanthracene derivatives, in which Ε of (1) is a CH 2 group, bis-(o-bromophenyl)methane was used as a starting material rather than the corresponding dichloro compound [4,5].…”

Section: Synthesis Of 55-diphenyi-1011-dihydro-5-h-dibenzo[bf]plummentioning

confidence: 99%

“…In the synthesis of 9,10-dihydro-9plumbaanthracene derivatives, in which Ε of (1) is a CH 2 group, bis-(o-bromophenyl)methane was used as a starting material rather than the corresponding dichloro compound [4,5]. This method is more attractive than those previously reported in the literature [5,7] ,10-Dihydrophenazaplumbine derivatives, in which Ε denotes a nitrogen atom with an alkyl substituent R, can be obtained according to eq.(4). (2) in an overall yield of c. 30% [6].…”

Section: Synthesis Of 55-diphenyi-1011-dihydro-5-h-dibenzo[bf]plummentioning

confidence: 99%

See 1 more Smart Citation

Synthesis and Multinuclear NMR Properties of Sixmembered Heterocyclic Organolead Compounds

Beelen¹,

Rijn²,

Heringa³

et al. 1997

Main Group Metal Chemistry

View full text Add to dashboard Cite

Several six-membered heterocyclic organolead compounds were synthesized from the appropriate di-Grignard resp. organodilithio compounds and a (diorgano)lead dihalide. The compounds were investigated by multinuclear NMR spectroscopy. Variable temperature 1 H NMR measurements revealed a conformational equilibrium. In the 13 C and 207 Pb NMR spectra specific effects caused by the presence of a lead atom in the ring system could be observed. IntroductionIn several previous studies we had investigated some aspects of the chemistry of cyclic organolead compounds, including five-membered ring compounds, in particular [2,3]. Subsequently we studied several six-membered cyclic organolead compounds of the general type (1) and the results are presented here. We were particularly interested in the effects of variation of the element Ε on the multinuclear NMR properties. Results on 10,10-dimethylphenoxaplumbin, in which Ε denotes an oxygen atom and R is CH 3 , have been previously published [1]. Materials and Methods1 H and 13 C NMR spectra were recorded on a JEOL-PFT-100 NMR spectrometer. 207 Pb NMR spectra were recorded on a Bruker WH 90 multinuclear spectrometer. Experimental details on the recording and assignments of the various spectra have been published elsewhere [24,36]. All synthetic reactions were carried out under dry nitrogen. The solvents diethylether (ether) and tetrahydrofuran (THF) were distilled from lithiumaluminiumhydride before use. For more experimental details see ref.[39]. Synthesis of bis-(o-bromophenyl)methane [6]A solution of 25.0 g of o-dibromobenzene (0.106 mol) and 19.9 g of 1,2-dibromoethane (0.106 mol) in 125 ml of ether was added dropwise to 5.15 g of magnesium (0.212 mol) in 15 ml of ether which was stirred magnetically. External cooling was applied by means of an ice bath and the reagents were added at such a rate that the temperature of the reaction mixture did not exceed 10°C. After the reaction was completed (ca. 3 h) the mixture was stirred for another 10 min. and at 0°C 19.7 g of o-bromobenzaldehyde (0.106 mol) was added dropwise. After refluxing for 2 h the mixture was cooled down to room temperature and hydrolysed with an aqueous ammonium chloride solution. The ether layer was isolated and the water layer was extracted with a 100 ml portion of ether. The combined ether fractions were dried over anhydrous magnesium sulfate. After filtration and evaporation, a yellow oil of 2,2'-dibromodiphenylmethanol was obtained. ©Part III, see ref.[1] Abstract R' R (1) 37 Brought to you by | Purdue University Libraries

show abstract

“…The losing of the fourth substituent group usually led to the formation of cation, radical or else anion of central carbon, in most cases, if sterically permitted, which would also exist in conjugated tautomeric forms [1,2]. Early researches on the ortho-substituted TAMs are less active because introducing substituents to the ortho position of aryl arms usually needs multi-step reactions [8,9]. The steric hindrance of ortho-nitro groups were reported decreasing the stabilization and influencing the intrinsic reactivity of the conjugated carbanions [10,11].…”

Section: Introductionmentioning

confidence: 98%