## Abstract Rhodium‐catalyzed carbonylation of methanol at mild temperature and pressure has been developed for small‐ and large‐scale preparations of the carbon isotope isomers of acetic acid.
Syntheses with stable isotopes: Thymine-2,6-13C2
✍ Scribed by Carolyn M. Redwine; Thomas W. Whaley
- Publisher
- John Wiley and Sons
- Year
- 1979
- Tongue
- French
- Weight
- 227 KB
- Volume
- 16
- Category
- Article
- ISSN
- 0022-2135
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
A three‐step synthesis of thymlne‐2,6‐^13^C~2~ from urea‐^13^C, sodium cyanide‐^13^C, and α‐bromopropionic acid is described. The last reaction involves hydrogenation of α‐cyano‐^13^C‐propionylurea‐^13^C in aqueous acetic acid and produces thymine‐2,6‐^13^C~2~ in 50–60% yield. The mechanism of this reaction is discussed.
📜 SIMILAR VOLUMES
## Abstract Sodium cyanide‐ ^13^C has been prepared in 65–70% overall yield from carbon‐^13^C monoxide in a three‐step synthesis proceeding through isopropyl formate‐ ^13^C and formamide‐ ^13^C as intermediates. Several. methods for the dehydration of formamide have been investigated.
## Abstract Acetylene‐^13^C~2~ has been prepared from carbon‐^13^C dioxide and molten lithium following hydrolisis of the resulting lithium carbide‐^13^C~2~. The stable ethylenediamine complex of lithium acetylide‐^13^C~2~ has been obtained from the reaction of acetylene‐^13^C~2~ with __N__‐lithioe
The synthesis of DL-2-amino-3-methyl-Cbutanoic-3,4-13C3 acid (DL-valine-13Cj) is described. Acetonitrile-2-13C was converted to 2methyl-13C-Z-thiazoline, which was dialkylated with methyl -13C iodide to give 2-(isopropyl-13C3) -2 -thiazoline. hydrolysis o f the isopropylthiazoline afforded 2-methyl
## Abstract Urea has been prepared from the reaction of carbon monoxide and ammonia in the presence of sulfur. The reaction has been applied to the synthesis of urea‐^13^C, urea‐^12^C, and urea‐^13^C‐^15^N~2~.
## Abstract The synthesis of a mixture of D‐glucose‐6‐^13^C and 1,6‐anhydro‐β‐L‐idopyranose‐6‐^13^C and their resolution by column chromatography are described. The Kiliani reaction of hydrogen cyanide‐^13^C with 5‐aldo‐1, 2‐0‐isopropylidene‐D‐xylo‐pentofuranose afforded epimeric cyanohydrins. Rapi