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141.
142.
An easily accessible ionic liquid, 1-methyl-3-pentylimidazolium fluoroborate, [pmIm]BF4, has been demonstrated to be an efficient catalyst as well as reaction medium for the stereoselective debromination of a variety of structurally diverse vicinal-dibromides to the corresponding (E)-alkenes in high yields under microwave irradiation. This reaction does not require any organic solvent and any metal or any conventional reducing agent, and the ionic liquid is recycled without any appreciable loss of its catalytic efficiency. 相似文献
143.
A variety of structurally diverse epoxides undergo facile cleavages by ionic liquid, [AcMIm]X without any catalyst and solvent to produce the corresponding vicinal halohydrins in high yields. The cleavages are considerably fast and highly regioselective. 相似文献
144.
Bhatt PM Ravindra NV Banerjee R Desiraju GR 《Chemical communications (Cambridge, England)》2005,(8):1073-1075
Saccharin, acting as a weak acid, forms salts with basic APIs and these salts have the desirable property of enhanced water solubility. 相似文献
145.
146.
147.
A convenient method for the conversion of electron rich benzylic hydrocarbons to carbonyl compounds is reported. 相似文献
148.
The effective matrix elements in (d
3/2−f
7/2)2 configuration have been recently defined by Erskineet al. and Sherret al. assuming shell clcsures for S32 and Ca40. We have attempted to verify whether this empirically deduced (d
3/2−f
7/2)2 interaction permits thed
3/2 shell to remain closed when nucleons are added to Ca40. It is found that the Erskine interaction gives rise to ground states of thef
7/2 shell nuclei in which thed
3/2 orbit is completely filled. However that interaction over-binds Ca40. If the centroid of the (d
3/2)2 interaction is modified to fit the Ca40 binding energy, the ground states of Cr48 and Fe52 become deformed and thed
3/2 orbit is not completely filled. 相似文献
149.
The separation betweenT=0 andT=1 centroids of the empirical effective interaction is fairly large for the (d
3
2/−1
f
7/2)JT particle-hole interaction as compared to nearby (f
7/2)2
JT and (d
5/2)2
JT particle-particle interactions. This interesting feature of the empirical effective interaction is shown to arise as a consequence
of renormalization of the effective interaction as one truncates the configuration space from (s−d)−1(f−p)1 to (d
3
2/−1
f
7/2) and from (f−p)2 and (s−d)2 configurations to (f
7/2)2 and (d
5/2)2 respectively. 相似文献
150.
Shri Nivas Bhatt 《Rendiconti del Circolo Matematico di Palermo》1962,11(2):237-244
The author has established that if [λn] is a convex sequence such that the series Σn -1λn is convergent and the sequence {K n} satisfies the condition |K n|=O[log(n+1)]k(C, 1),k?0, whereK n denotes the (R, logn, 1) mean of the sequence {n log (n+1)a n}, then the series Σlog(n+1)1-kλn a n is summable |R, logn, 1|. The result obtained for the particular casek=0 generalises a previous result of the author [1]. 相似文献