Synthesis, crystal and molecular structure of [{C5Me5FeC5Me4CH2}+B{C6H3(CF3)2}4−], the first example of a structurally characterized primary ferrocenylcarbocation

Comparison of the bis(ferrocenylethynyl)phenylmethylium cation with bis(ferrocenylethenyl)methylium analogues

“…Brønsted or Lewis acids have been used to generate carbocations stabilised by one or more group 8 metallocenes from alcohol precursors [7,[23][24][25][26][27][28][29][30][31][32][33][34][35][36]. Indeed, [Fc 2 CCCFc] + -related to our target cations in featuring a ferrocenylalkynyl group -was obtained from protonation of Fc 2 C(OH)C"CFc, itself obtained from the reaction of FcC"CLi and Fc 2 CO [32,37].…”

Synthesis, structures and reactions of some metallocene alcohols

“…Structures were solved using SIR I R92 [46], with additional nonhydrogen atoms being located, where necessary, from difference Fourier maps. Full-matrix least square refinements were carried out against F (on all data for 8 and 9; on data with I > 2rðIÞ for (10)(11)(12) using CRYS-R YS -TALS TALS [47]. Chebychev polynomial weighting schemes (five-term for 8; three-term for (9)(10)(11)(12) were applied [48].…”

“…Full-matrix least square refinements were carried out against F (on all data for 8 and 9; on data with I > 2rðIÞ for (10)(11)(12) using CRYS-R YS -TALS TALS [47]. Chebychev polynomial weighting schemes (five-term for 8; three-term for (9)(10)(11)(12) were applied [48]. Details of the data acquisition and refinements are summarised in Table 1; complete crystallographic data for the structural analysis have been deposited with the Cambridge Crystallographic Data Centre, CCDC 210126-210130 for compound 8-12. In the structure of 9 the half-molecule containing the atom Fe(2) was modelled with a disordered tert-butyl group [C(32), C(34) and C(36) with 33% occupancy; C(33), C(35) and C(37) 67% occupancy].…”

“…Many have been synthesised as precursors to metallocenestablised carbocations, which can be described as (g 5 -cyclopentadienyl-g 6 -fulvene)metal(II) and whose structures and bonding have been extensively studied [1][2][3][4][5][6][7][8][9][10][11][12], and which have themselves served as synthetic intermediates [12][13][14][15][16][17]. Metallocenyl alcohols have also been used as intermediates in the synthesis of chiral ligands for asymmetric catalysis [18,19].…”

Selective synthesis of (3-ferrocenylprop-2-en-1-yl)triphenylphosphonium iodide: crystal structure determination of two polymorphs

“…Carbocation C is indeed a very reactive reaction intermediate, like all -ferrocenyl carbocations (Gleiter et al, 1972;Allenmark, 1974;Richards et al, 1994;Taudien et al, 1995), but its stability is strongly increased by the positive chargestabilizing ability of ferrocene through an electron transfer from the metal atom to the -carbocationic centre (Kreindlin et al, 2000). In the presence of sufficient base, the ammonium cations are deprotonated to the corresponding allylamines, which do not interconvert (Bouchene et al, 2017).…”