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81.
Oxidation of several linear conjugated dienes with tellurium (IV) oxide and lithium bromide in acetic acid affords an isomeric mixture of the corresponding diacetoxyalkenes (1,2- and 1,4-addition products), 1,4-isomer being highly selectively produced when the ratio of LiBr/TeO2, is 5–10. 相似文献
82.
Y.J. Uemura R.S. Hayano J. Imazato N. Nishida T. Yamazaki 《Solid State Communications》1979,31(10):731-734
The zero-field spin relaxation function of μ+ observed in ZrH2 has revealed that the second moment of the nuclear dipolar broadening is five times larger than the high-field value. This experiment clearly demonstrates the recovery of the non-secular part of dipolar interaction between unlike spins. A general expression of zero-field relaxation function is presented to account for a slow modulation of random fields on μ+ found at room temperature. 相似文献
83.
The addition of arylboronic acids 1 to azodicarboxylates 2 in the presence of a catalytic amount of a copper salt under mild reaction conditions gives aryl-substituted hydrazines 3 in high yields. The reaction is tolerant of a wide variety of functional groups. 相似文献
84.
Masaki Kita Tomoyuki Koyama Hiroshi Matsumoto Daisuke Uemura 《Tetrahedron letters》2005,46(49):8583-8585
The muricid gastropods genus Drupella are known to be voracious coral predator. Outbreaks of them have accelerated significant destruction on coral reefs, but its precise mechanism is poorly understood. Here, we describe the identification of montiporic acids C (1) and A (2) isolated from sea water extracts of the coral Montipora sp., which showed potent feeding-attractant activity toward D. cornus. 相似文献
85.
Uemura T Kitagawa K Horike S Kawamura T Kitagawa S Mizuno M Endo K 《Chemical communications (Cambridge, England)》2005,(48):5968-5970
The first radical polymerisation of styrene in porous coordination polymers has been carried out, providing stable propagating radicals (living radicals), and a specific space effect of the host frameworks on the monomer reactivity is demonstrated. 相似文献
86.
87.
Treatment of several cyclic olefins, β-pinene, allylbenzene, and estragole with palladium(II) salt in acetic acid in the presence of t-butyl hydroperoxide and tellurium(IV) oxide afforded mainly the corresponding allylic acetates. The reaction proceeded catalytically with palladium(II) salt, t-BuOOH working as a reoxidizing agent. 相似文献
88.
89.
90.
[reaction: see text] The reaction of heteroaromatic compounds with propargylic carboxylates in the presence of a catalytic amount of [RuCl(2)(CO)(3)](2) or PtCl(2) gives trienes in good yields. The key intermediate is an electrophilic (1-acetoxylvinyl)carbene complex generated from the activated propargylic acetates with transition metals. 相似文献