𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Cage reactions in the photolysis of 2,2,4,4-tetramethyl-3-pentanone

✍ Scribed by E. B. Abuin; M. V. Encinas; S. Díaz; E. A. Lissi

Publisher
John Wiley and Sons
Year
1984
Tongue
English
Weight
472 KB
Volume
16
Category
Article
ISSN
0538-8066

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

The product quantum yields in the photolysis of 2,2,4,4‐tetramethyl‐3‐pentanone have been measured in homogeneous solvents of different viscosities, in micellar solutions of cetyltrimethylammonium chloride and sodium dodecyl sulfate, and in dioctadecyl ammonium chloride vesicles.

The product quantum yield in n‐heptane was found to be 1. This value decreases to 0.5 in paraffin oil as a consequence of geminate recombination. In the presence of free radical scavengers, the extent of geminate disproportionation can be evaluated from the yields of isobutene and 2,2‐dimethyl propionaldehyde. From these yields and the geminate recombination yields the total amount of geminate processes and the disproportionation‐to‐combination ratio for caged radicals are estimated. It is found that micelles provide the most efficient cages. In these media only about 10% of the radicals avoid cage processes. The disproportionation‐to‐combination ratio of tert‐butyl and pivaloyl radicals was found to be extremely media dependent. The measured values ranged from about 0.2 in paraffin oil to 0.8 in cetyltrimethylammonium chloride micelles.

📜 SIMILAR VOLUMES

Sulfurization of Thiones: 2,2,4,4-Tetram
Sulfurization of Thiones: 2,2,4,4-Tetramethyl-3-thioxocyclobutanone
✍ Huisgen, Rolf ;Rapp, Jochen ;Huber, Helmut 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 759 KB

## Abstract By treatment with elemental sulfur and a catalytic amount of sodium thiophenolate in acetone at room temp., the title compound 9 is converted to the bis‐spiro derivatives of 1,2,4,5‐tetrathiane, 13, and 1,2,3,5,6‐pentathiepane, 14. The initial attack by the phenyl oligosulfide anion tak

ChemInform Abstract: Sulfurization of Th
ChemInform Abstract: Sulfurization of Thiones: 2,2,4,4-Tetramethyl-3-thioxocyclobutanone.
✍ R. HUISGEN; J. RAPP; H. HUBER 📂 Article 📅 2010 🏛 John Wiley and Sons ⚖ 29 KB 👁 1 views

Sulfurization of Thiones: 2,2,4,4-Tetramethyl-3-thioxocyclobutanone. -The conformational changes of the bis-spiro derivatives (II) and (III), obtained from the title reaction, are evaluated by dynamic 1H and 13C NMR spectra. Their fragmentation pattern is discussed by mass spectroscopy and their th