Protonation of chromium tricarbonyl complexes of triphenylsilanol and triphenylcarbinol: synthetic, x-ray crystallographic, and NMR study of (Ph3SiOH)[Cr(CO)3]n (n = 1-3) and of (Ph3COH)Cr(CO)3

An NMR study of the rotational barriers in cobalt-stabilized carbocations: X-ray crystal structures of (η4-C4Ph4)Co-(η5-C5H4R), where R is CH3CO, CHO, CH(tBu)OH

“…Typically, when going from (C 6 H 5 -CPh 2 OH)Cr(CO) 3 to [(C 6 H 5 -CPh 2 ) Cr(CO) 3 ] þ , the a-carbon resonances are found at 79.7 d and 185.8, respectively, a Dd value of 106.1 ppm [31]. On the other hand, when the majority of the positive charge are ever more delocalized onto the organometallic moiety, the 13 [19,32].…”

Delocalized bonding in tetrahedral organo-transition metal clusters: an EHMO study of metal vertex rotations in Co2Fe(CO)9S, CpMoCo2(CO)8CR, and in Cp2Mo2(CO)4(RC≡CR)

“…Subsequently, this approach was used in an analysis of a series of organometallic derivatives of triphenylsilanol (19). Furthermore, in a study from this laboratory it has been reported that the calculated pathway for antarafacial migration of a CH,' fragment between the molybdenum sites in cation clusters of the type [Cp,Mo,(CO),(RC=C-CR,)]' is paralleled beautifully by the available structural data on such cations (20).…”

Arenechromiumtricarbonyl complexes of silyl(germyl)(stannyl)- and silyl(germyl)(plumbyl)methanes including the unexpected formation of arenechromiumtricarbonyldimethylsilanol, (η6-C6H5)Cr(CO)3SiMe2OH

“…The fact that there appears to be no Ge-CH cleavage supports this suggestion and is currently being tested. It is well documented that the benzylic carbon is activated by the chromiumtricarbonyl species to produce stable benzylic cations [11]. The electrochemical studies of the (organosilyl)arenechromium tricarbonyl complexes also suggests the stability of the oxidized (organosilyl)arenechromiumtricarbonyl compounds which is solvent and substituent depended [12].…”

“…The torsion angles C ipso -ring centroid–Cr-C n (O) ( n = 7, 8 and 9 in Fig.1) are −168.40, +72.60 and −50.95 degrees respectively, the tripodal arrangement is about 12° from the ideally eclipsed conformation (torsion angles −60, +60 and +180 degrees) relative to the para and two ortho carbon atoms in the ring. The Si-C bond distances, in the range of 1.847–1.878 Ǻ, and a Si-O bond distance of 1.652(1) Ǻ are typical of organosilanols [11, 13–18]. The O-Si-C bond angles between 108.22–108.87° signify essential tetrahedral geometry and compare well with the reported values for its diphenyl analog, {(η 6 –C 6 H 5 )Cr(CO) 3 }Ph 2 SiOH, 8 [11].…”