The first approach to optically active 2,2′-bipyridine alkyl sulfoxides

A Convenient Approach to 16‐, 19‐, and 22‐Membered 2,2′‐Bipyridine Thiacrown Ethers and Their Conformation Preferences

“…[14] In this work, we report a new approach to 1:1 thiacrown ether macrocycles and their sulfoxides incorporating a cyclopenteno[c]2,2Ј-bipyridine subunit, as well as X-ray crystallographic analysis of the target ligands. Our preliminary findings [15] and these studies suggest that this approach is fairly general for the preparation of large-sized rings, that is, rings having 13-22 or more atoms.…”

“…N1A-C2A-C2B-N1B 0.4(2) -31.9 N1B-C6B-S10B-C11B -1.66 (17) 7.3 N1A-C6A-S10A-C11A -8.5(6) 2.5 C6B-S10B-C11B-C12B 174.06 (15) 98.6 C6A-S10A-C11A-C12A -141.7(9) -148.6 S10B-C11B-C12B-O13B -179.69(13) -178.8 S10A-C11A-C12A-O13A -54.0(12)…”

“…Spectral data is described in a previous communication. [15] 1, 11- Bis(1,2,4-trizin-3-ylsulfanyl) Bis(1,2,4-trizin-3-ylsulfanyl)-3,6,9,12- 5-Bis(1,2,4-trizin-3 General Procedure for the Preparation of 5,5Ј-Bi-1,2,4-triazine-Containing Thiamacrocycles 4a-c and 10: A suspension of compound 3a-c or 9 (0.59 mmol) in water (134 mL) was stirred at 40°C until complete dissolution. After cooling to room temperature, potassium cyanide (0.137 g, 2.12 mmol) was added as a solid, and the resulting mixture was stirred for the period of time indicated in Table 1.…”

“…Furthermore, these ligands may constitute a valuable starting material for the synthesis of bpy chiral sulfoxides as catalysts in asymmetric reactions. [12] However, the study of the metal-complexing ability of these interest-4868 cycles 5a-c were oxidized to nonracemic monosulfoxides 6a-c by using Davis' oxaziridine and tested in the asymmetric addition of the diethylzinc to benzaldehyde. The crystal structure determinations of 5a-c and 6b and theoretical calculations at the DFT/B3LYP/6-311G** level were used to establish their cis or trans conformations in the solid state and the gas phase.…”

Self-disproportionation of enantiomers (SDE) of chiral sulfur-containing compounds via achiral chromatography

“…This is based on the fact that the reported enantiomeric excess values differ very much for derivatives having very similar structures. Among them there are papers co-authored by one of us [99][100] devoted to the asymmetric oxidation of 2,2'-bipyridine alkyl sulfides 15a-e to non-racemic 2,2'-bipyridine alkyl sulfoxides 16a-e and bis-sulfoxides 17a-e using either (+)- (8,8-dichlorocamphorylsulfonyl) oxaziridine (method A) 101 or the Kagan reagent (method B) 91 (Scheme 9). Scheme 9.…”