Oxo‐Entity‐Controlled Diastereomer Peculiarity of Rhenium(V) Complexes ReOX₂(P~O)py [X = Cl, Br, I; P~O = (OCMe₂CMe₂O)POCMe₂CMe₂O(1–); py = pyridine]: Synthesis and Molecular and Crystal Structural Characterization

Abstract

-6-15] complexes can be obtained concomitantly, while for X = I only a trans complex can be afforded. Molecular structures were characterized using NMR IR and UV/Vis spectroscopic methods with the aid of DFT computational analysis and were ultimately corroborated by the single-crystal X-ray diffraction method. These analyses revealed that the most stable diastereomers involve an O=Re(-O~P) oxo arrangement in an axial disposition reinforced with a phosphorus ligating atom mutually cis due to extensive π-bonding both for chiral cis

Spontaneous resolution, whence and whither: from enantiomorphic solids to chiral liquid crystals, monolayers and macro- and supra-molecular polymers and assemblies

“…For instance, the formation of Pasteur's salt is in competition with a metastable racemic compound which limits entrainment, 54 a situation which is also true for other racemates, 55 such as the diastereoisomerism displayed by rhenium(V) complexes can lead to conglomerates or racemic compounds. 56 The transition between a conglomerate and a true racemate has been observed in the compound [{H 3 N(CH 2 ) 2 S-S(CH 2 ) 2 NH 3 }PbI 5 ]H 3 O. 57 The conglomerate -which was crystallised by slow cooling under solvothermal conditionsis comprised of zigzag chains of lead iodide octahedra (which share corners) with the organic dication in between, packed in the space group P2 1 .…”

Asymmetric autocatalysis: crystallization-induced highly enantioselective synthesis of a conglomerating oxo-rhenium(V) complex

“…[50][51][52] The cis-with trans-equilibrium reported in those papers is further discussed here in connection with three precursor reactions used to make the desired equilibrating rhenium complex. We focus on the synthesis, illustrated in Scheme 1, of chiral cis-ReOCl 2 (P $ O)py cis-1 as a conglomerate of C-(+) 589 and A-(À) 589 enantiomers, which can be accomplished from optically inactive substrates in several ways.…”

“…In a chelation reaction (1), achiral trans-ReOCl 2 (OEt)py 2 and the optically inactive spirophosphorane HP $ O yield a racemic mixture of cis-1 with the minor formation of trans-1 owing to cistrans equilibration (3), that is, isomerization reaction. 50,52 Secondly, cis-1 can be obtained as a result of the substitution of pyridine for the monodentate ligand L in ReOX 2 (P $ O)L (L = PPh 3 , OPPh 3 ), (2). à Finally, cis-1 can be attained directly from trans-1 through an intrinsic isomerization reaction (3).…”

cis-Dichlorido[2,3-dimethyl-3-(4,4,5,5-tetramethyl-1,3,2λ5-dioxaphospholan-2-yloxy)butan-2-olato-κ2O,P]oxido(triphenylphosphane-κP)rhenium(V)

“…For related structures and further discussion, see: Głowiak et al (1998Głowiak et al ( , 2000; Rybak et al (2005). For typical bond lengths in coordination complexes, see: Orpen et al (1989).…”

“…(2012). E68, m605-m606 [doi:10.1107/S1600536812015565] Dichlorido[2,3-dimethyl-3-(4,4,5,5-tetramethyl-1,3,2λ (Rybak et al, 2005). In this paper we report the synthesis and crystal structure of the title oxidorhenium(V) complex, obtained starting from an analogous trans complex (Głowiak et al 2000).…”