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791.
The treatment of N‐benzylideneaniline ( 1a ) with a half‐equivalent of lanthanum metal and a catalytic amount of iodine gave the reductive dimerization product of 1a , a vic‐diamine, in good yield. Various vic‐diamines were synthesized from aldimines in this manner in moderate to good yields. Our findings suggest that electrons of a zero‐valent lanthanum metal were efficiently utilized in this reductive dimerization. In the reaction of ketimines, however, a similar reductive dimerization did not take place, and the corresponding amines were formed as the sole products. © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:131–135, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/hc.10007 相似文献
792.
793.
William J. Bailey Paul Y. Chen Shuh-Cheng Chen Wen-Bin Chiao Takeshi Endo Benjamin Gapud Vijaya Kuruganti Yin-Nian Lin Zhende Ni Cai-Yuan Pan Scott E. Shaffer Luann Sidney Shang-Ren Wu Noboru Yamamoto Noboro Yamazaki Kazuya Yonezawa Lin-Lin Zhou 《Macromolecular Symposia》1986,6(1):81-100
Since a carbon-oxygen double bond is considerably more stable than a carbon-carbon double bond, it has been possible to use this driving force to promote free radical ring-opening polymerization of unsaturated heterocyclic compounds. This process, for the first time, has permitted the introduction of functional groups, such as esters, amides and carbonates, into the backbone of addition polymers. Hydrolysis of the copolymers with common monomers produced oligomers capped with hydroxyl, amino or carboxylic acid groups. The presence of an ester group in a copolymer, such as in a copolymer of ethylene, render the copolymer biodegradable. 相似文献
794.
Yutaka Nishiyama Susumu Katsuen Hiroshi Jounen Sawako Hamanaka Akiya Ogawa Noboru Sonoda 《Heteroatom Chemistry》1990,1(6):467-474
Selenium has been found to be an excellent catalyst for the reductive debromination of some organic bromides with carbon monoxide and water: vic-dibromoalkanes and α-halo ketones can be reduced to the corresponding alkenes and ketones respectively in moderate to high yields. 相似文献
795.
Takumi Mizuno Ikuzo Nishiguchi Tsuneaki Hirashima Noboru Sonoda 《Heteroatom Chemistry》1990,1(2):157-159
Carbon oxide sulfide was easily generated upon heating of amine salts of carbamothioic acids at 85°C which were produced in situ from amines, carbon monoxide, and elemental sulfur in the presence of a catalytic amount of selenium under mild conditions. 相似文献
796.
797.