4291-99-0Relevant academic research and scientific papers
Stereoselective synthesis of δ-lactones from 5-oxoalkanals via one-pot sequential acetalization, tishchenko reaction, and lactonization by cooperative catalysis of samarium ion and mercaptan
Hsu,Fang
, p. 8573 - 8584 (2007/10/03)
By the synergistic catalysis of samarium ion and mercaptan, a series of 5-oxoalkanals was converted to (substituted) δ-lactones in efficient and stereoselective manners. This one-pot procedure comprises a sequence of acetalization, Tishchenko reaction and lactonization. The deliberative use of mercaptan, by comparison with alcohol, is advantageous to facilitate the catalytic cycle. The reaction mechanism and stereochemistry are proposed and supported by some experimental evidence. Such samarium ion/mercaptan cocatalyzed reactions show the feature of remote control, which is applicable to the asymmetric synthesis of optically active δ-lactones. This study also demonstrates the synthesis of two insect pheromones, (2S,5R)-2-methylhexanolide and (R)-hexadecanolide, as examples of a new protocol for asymmetric reduction of long-chain aliphatic ketones.
The Reaction of Organoboranes with Lithium Salts of Trisylhydrazones of Cycloalkanones Followed by Treatment with Iodine
Baba, Tsutomu,Avasthi, Kamlakar,Suzuki, Akira
, p. 1571 - 1572 (2007/10/02)
The titled reaction proceeds smoothly under mild conditions to give corresponding 1-alkylcycloalkenes in excellent yields.The overall reaction provides a convenient synthetic procedure of cycloalkenes for cycloalkanones, with various alkyl substituents readily available by means of hydroboration.
