𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Contrasting conformational behavior of 5-methylsulfonyl-1,3-dioxane and -1,3-dithiane in the minimization of steric and electrostatic repulsive interactions

✍ Scribed by J.Samuel Cruz-Sánchez; Eusebio Juaristi

Publisher
Elsevier Science
Year
2002
Tongue
French
Weight
206 KB
Volume
43
Category
Article
ISSN
0040-4039

No coin nor oath required. For personal study only.

✦ Synopsis

The preparation of novel 1,3-dithiane derivatives, cis-and trans-2-tert-butyl-5-methylsulfonyl-1,3-dithiane, was achieved by acid-catalyzed condensation of 2-methylsulfonyl-1,3-propanedithiol with pivalaldehyde. The former dithiol was obtained from allylmethylsulfide via the Knochel-Normant bromination-rearrangement protocol. Configurational and conformational assignment of cis-and trans-5 was based on 1 H NMR analysis, and revealed that the trans isomer adopts a normal chair conformation. By contrast, cis-5 adopts a twist-boat conformation in order to minimize the steric and electrostatic repulsive interactions that an axial methylsulfonyl group engenders. Chemical equilibration cis-5 X trans-5 shows the latter to be more stable by 1.50 kcal/mol.

📜 SIMILAR VOLUMES

On the NMR spectrum of 1,3-oxathiane-3-o
On the NMR spectrum of 1,3-oxathiane-3-oxide: A contrast between the conformational preference of the sulphinyl oxygen in 1,3-oxathiane-3-oxide and in 1,3-dithiane-1-oxides
✍ Knut Bergesen; Michael J. Cook; Alan P. Tonge 📂 Article 📅 1974 🏛 John Wiley and Sons 🌐 English ⚖ 182 KB

## Abstract The 100 MHz spectrum of 1,3‐oxathiane‐3‐oxide is reported. Parameters obtained from first order analyses are interpreted in terms of an absence of a conformational preference of the SO bond at 38°C, but an axial preference at low temperatures. The behaviour contrasts with that found pr