(R)-3,3′-Diiodo-2,2′-bis(methoxymethoxy)-1,1′-binaphthalene(cas: 189518-78-3) belongs to organic iodides. The carbon-iodine bond is weaker than other carbon-halogen bonds due to the poor electronegative nature of the iodine atom. Category: iodides-buliding-blocks Alkyl iodides react at a faster rate than alkyl fluorides due to the weak C-I bond.
Category: iodides-buliding-blocksOn November 11, 1998 ,《Molecular recognition of pyranosides by a family of trimeric, 1,1′-binaphthalene-derived cyclophane receptors》 appeared in Helvetica Chimica Acta. The author of the article were Baehr, Anja; Droz, Anne Sophie; Puentener, Martin; Neidlein, Ulf; Anderson, Sally; Seiler, Paul; Diederich, Francois. The article conveys some information:
The synthesis and carbohydrate-recognition properties of optically active cyclophane receptors I [R = PhCH2O, R1 = H; R, R1 = H; R = H, R1 = Ph(CH2)2], in which 3 1,1′-binaphthalene-2,2′-diol spacers are interconnected by 3 1,3-butadiyne-1,4-diyl linkers, are described. The macrocycles all contain highly preorganized cavities lined with 6 convergent OH groups for H-bonding and complementary in size and shape to monosaccharides. The preparation of the more planar, D3-sym. receptors (R,R,R)-I (R = PhCH2O, R1 = H) and (S,S,S)-I [R = PhCH2O, R1 = H; R, R1 = H; R = H, R1 = Ph(CH2)2] involved as key step the Glaser-Hay cyclotrimerization of the corresponding OH-protected 3,3′-diethynyl-1,1′-binaphthalene-2,2′-diol precursors, which yielded tetrameric and pentameric macrocycles in addition to the desired trimeric compounds The synthesis of the less planar, C2-sym. receptors (R,R,S)-I (R, R1 = H) and (S,S,R)-I [R = H, R1 = Ph(CH2)2] proceeded via 2 Glaser-Hay coupling steps. The flat D3-sym. receptors (R,R,R)- and (S,S,S)-I (R = PhCH2O, R1 = H) formed 1:1 cavity inclusion complexes with octyl 1-O-pyranosides in CDCl3 (300 K) with moderate stability (ΔG0 ≈ -3 kcal mol-1) as well as moderate diastereo- [Δ(ΔG0) ≤ 0.7 kcal mol-1] and enantioselectivity [Δ(ΔG0) = 0.4 kcal mol-1]. Stoichiometric 1:1 complexation by (S,S,S)-I [R, R1 = H; R = H, R1 = Ph(CH2)2] could not be investigated by 1H-NMR binding titrations, due to very strong signal broadening. This broadening of the 1H-NMR resonances is presumably indicative of higher-order associations, in which the planar macrocycles sandwich the carbohydrate guests. The less planar C2-sym. receptor (S,S,R)-I [R = H, R1 = Ph(CH2)2] formed stable 1:1 complexes with binding free-enthalpies of up to ΔG0 = -5.0 kcal mol-1. With diastereoselectivities up to Δ(ΔG0) = 1.3 kcal mol-1 and enantioselectivities of Δ(ΔG0) = 0.9 kcal mol-1, (S,S,R)-I [R = H, R1 = Ph(CH2)2] is among the most selective artificial carbohydrate receptors known. In the experimental materials used by the author, we found (R)-3,3′-Diiodo-2,2′-bis(methoxymethoxy)-1,1′-binaphthalene(cas: 189518-78-3Category: iodides-buliding-blocks)
(R)-3,3′-Diiodo-2,2′-bis(methoxymethoxy)-1,1′-binaphthalene(cas: 189518-78-3) belongs to organic iodides. The carbon-iodine bond is weaker than other carbon-halogen bonds due to the poor electronegative nature of the iodine atom. Category: iodides-buliding-blocks Alkyl iodides react at a faster rate than alkyl fluorides due to the weak C-I bond.
Referemce:
Iodide – Wikipedia,
Iodide – an overview | ScienceDirect Topics – ScienceDirect.com