3.4-Dihydro-l, 2, 3, 4-tetramethyl- pentafulvalene and its Conversion to Ferrocenes
نویسندگان
چکیده
Pentafulvenes have been widely used as starting compounds for the synthesis of transition-metal cyclopentadienyl (Cp) compounds, not least the metallocenes [1], The route is based on the unique reactivity of the exocyclic methylene carbon atom and furnishes two types of substituted Cp deriva tives depending on the anion that attacks the fulvene. If the anion (mostly carbanion, [R3]~ in Scheme 1) is sufficiently nucleophilic, alkylated Cp anions like A result [2]; if the anion acts as a base (e. g. after sterically screening the nucleophi lic center), vinyl-Cp anions like B are obtained [3].
منابع مشابه
Crystallography and magnetism of radicals with hindered hydroxyl groups: 2-(3,5-di-tert-butyl-4-hydroxyphenyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl and 2-(3,5-di-tert-butyl-4-hydroxyphenyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-1-oxyl.
Radicals form networks of OH... ON and OH...Me(nitroxide) interactions. In 2, a frustrated network forms with insufficient N-O units to form extended chain interactions. The magnetism of 1 fits a 1-D Heisenberg model with J/k=-25 J mol(-1), while 2 shows more complex exchange behaviour consistent with its disordered crystal lattice.
متن کاملC,O-dialkylation of Meldrum's acid: synthesis and reactivity of 1,3,7,7-tetramethyl-4H,10H-6,8,9-trioxa-2-thiabenz[f]azulen-5-one.
Reaction of Meldrum's acid with 3,4-bis(chloromethyl)-2,5-dimethylthiophene (1) or 3,4-bis(bromomethyl)-2,5-dimethylthiophene (2) produces the kinetically favored C,O-dialkylation product, 1,3,7,7-tetramethyl-4H,10H-6,8,9-trioxa-2-thiabenz[f]azulen-5-one (4). Recrystallization of 4 from refluxing methanol results in the methanolysis product 5-(4-methoxymethyl-2,5-dimethylthiophen-3-ylmethyl)-2,...
متن کاملOligomerization of 3,5-dimethyl benzyl alcohol promoted by clay: experimental and theoretical study.
Linear oligomerization of 3,5-dimethyl benzyl alcohol is induced by a montmorillonite clay (Tonsil Optimum Extra), producing 1,3,5,7-tetramethyl-9,10-dihydro-anthracene, which, by loss of protons results in the product 1,3,5,7-tetramethylanthracene. It was also found that the compounds 4-(3´,5´-dimethylbenzyl)-1,3,5,7-tetramethyl-9,10-dihydroanthracece and 4-(3´,5´-dimethylbenzyl)-1,3,5,7-tetra...
متن کاملA New Method for the Synthesis of Heterospin Complexes
The interaction of binuclear Co(II) pivalate [Сo2(H2O)Piv4(HPiv)4] with nitronyl nitroxide HL1 (2-(2-hydroxy-5-nitrophenyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole3-oxide-1-oxyl) in organic solvents led to the formation of a pentanuclear heterospin complex [Co5(Piv)4L14L22]. A nontrivial peculiarity of the complex is the presence of both the starting nitronyl nitroxide L1 and its deoxygena...
متن کاملl , 3 - Distanna - 2 - phospha - [ 3 ] ferrocenophanes - Synthesis , Reactivity and NMR Spectroscopic Properties
Z. Naturforsch. 54 b, 57-62 (1999); received July 28, 1998 Ferrocene, Tin, Phosphorus, NMR Data, Coupling Signs l,l,3,3-Tetramethyl-2-organo(R)-l,3-distanna-2-phospha-[3]ferrocenophanes [R = Me (2a), rBu (2b), CöH i i (2c), Ph (2d)] and one arsa-analogue 2d(As) were obtained from the reaction of l,l'-bis(chlorodimethylstannyl)ferrocene 1 with either bis(trimethylsilyl)methylphosphane or the dil...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2013