Diastereoselectivity in the self-assembly of As2L 2Cl2 macrocycles is directed by the As-π interaction

Virginia M. Cangelosi, Aaron C. Sather, Lev N. Zakharov, Orion B. Berryman, Darren W. Johnson

Research output: Contribution to journalArticlepeer-review

Abstract

The As-π interaction, in conjunction with reversible As-thiolate bond formation, is used to direct the self-assembly of dinuclear As2L 2Cl2 (L = a dithiolate) macrocycles that exist as equilibrium mixtures of both syn and anti diastereomers. The diastereomeric excess of these self-assembly reactions is controlled in a predictable manner by prudent choice of different achiral, isomeric ligands. A general method for the preparation of As2L2Cl2 macrocycles is established, and strategies to control the diastereoselective self-assembly of regioisomeric macrocycles in solution and the crystalline state are described. A mechanism for the interconversion between diastereomers (a slow process on the NMR time scale) is suggested, and variable-temperature NMR spectroscopic data show that the diastereomeric excess (de) decreases with increasing temperature. anti-As2(L2,6)2Cl2 crystallizes in monoclinic space group P21/n with a = 6.3949(13), b = 19.675(4), c = 10.967(2) Å, β = 106.817(3)°, and Z = 2. anti-As 2(L1,5)2Cl2 crystallizes in monoclinic space group P21/c with a = 6.813(4), b = 19.085(12), c = 10.277(6) Å, β = 107.788(10)°, and Z = 4. syn-As 2(L1,4)2Cl2·CHCl3 crystallizes in triclinic space group P1 with a = 19.313(4), b = 19.923(4), c = 24.508(5) Å, α = 78.110(4)°, γ = 78.860(5)°, γ = 89.183(5)°, and Z = 12. As2(L1.4)2Cl 2·C6H6 crystallizes in monoclinic space group P21/n with a = 10.3332(7), b = 34.375(2), c = 17.8593(12) Å, β = 98.9650(10)°, and Z = 8.

Original languageEnglish
Pages (from-to)9278-9284
Number of pages7
JournalInorganic Chemistry
Volume46
Issue number22
DOIs
StatePublished - Oct 29 2007

Fingerprint

Dive into the research topics of 'Diastereoselectivity in the self-assembly of As2L 2Cl2 macrocycles is directed by the As-π interaction'. Together they form a unique fingerprint.

Cite this