Thietane

• Thiacyclobutan
• Trimethylene sulfide

Colorless liquid

Liquid

1.028 g · cm -3 ( 20 ° C)

-73 ° C

94 ° C

199 hPa ( 48 ° C)

Soluble in ethanol, benzene

1.510 at 20 ° C.

Risk

24.7 kJ / mol

Template: Infobox chemical / molecular formula search available

Thietane, also called trimethylene sulfide, is the simplest sulfur-containing saturated four-membered heterocycle.

Representation

Thietane can be obtained in very poor yield from the reaction between 1,3 -dioxane -2-one and potassium thiocyanate. Byproducts of potassium cyanate and carbon dioxide.

A better synthetic route is given by the reaction of 1,3-dibromopropane and sodium sulfide.

Properties

Thietane is a colorless, unpleasant smelling liquid which boils under atmospheric pressure at 94.8 ° C. The vapor pressure function is given by Antoine corresponding log10 (P) = A- ( B / ( T C )) ( P in bar, T in K) with A = 4.14157, B = 1321.331 and C = -48 637 in the temperature range from 321.5 to 404.8 K. in solid phase two polymorphic crystal forms are formed where the Kristallfom II converts at -96 ° C in the Kristallforn I. The melting point is then at -73 ° C. The molecule is built not perfectly square but has a distorted structure. The bond angles at the sulfur is 78 °, whereas the opposite has a carbon bond angle of 97 °. The CS bond length is 185.1 pm, the C -C bond length of 154.9 pm.

Reactions

With nucleophiles thietane reacts with ring opening. So is, for example, from the reaction with n- BuLi an unsymmetrical thioethers.

The reaction with elemental halogens enables the representation at both chain ends of open-chain halogenated disulfides.