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91.
L. H. Klemm John N. Louris William Boisvert Clay Higgins Daniel R. Muchiri 《Journal of heterocyclic chemistry》1985,22(5):1249-1252
Thieno[3,2-b]pyridine ( 1 ) is oxidized to N-oxide 1a by means of m-chloroperoxybenzoic acid (83%). Compound 1a forms adducts with hydrogen chloride and picric acid and gives ring substitution alpha or gamma to the heteronitrogen atom. Thus, 1a plus nitric and sulfuric acids produces the 7-nitro-N-oxide 1m (63%), or plus phosphorus oxychloride gives a mixture of 5-chloro and 7-chloro ( 1j ) derivatives of 1 . Compound 1m is convertible into a variety of other derivatives of 1 , viz. 7-chloro-N-oxide, 1j , 7-bromo-N-oxide, 7-nitro and 7-amino. 5-Cyano- 1 , formed from 1a , is, in turn, transformed into a methyl imidate (93%), cyclic amidines, and a 5-tetrazolyl- 1 (91%). These results confirm the prediction that 1a , thieno[2,3-b]pyridine-4-oxide and quinoline 1-oxide should exhibit closely similar (i.e. analogous) chemical reactions. 相似文献
92.
Anthony D. Klemm 《Physics letters. A》1985,110(5):246-248
Exact closed expressions have been obtained for the first three partial waves of the two-particle density matrix for a hard-core pairwise interaction. 相似文献
93.
Ohne Zusammenfassung 相似文献
94.
Gamil Alhakimi Elisabeth Klemm 《Journal of polymer science. Part A, Polymer chemistry》1995,33(5):767-770
The tetrafunctional products 3 and 6 were synthesized via Diels-Alder reaction of bis(2-pyrone) with bismaleimides in mol ratio 1:7. The chemical structure of these products was determined by 1H-NMR spectroscopy; the high degree of purity was confirmed by means of elemental analysis. The cyclization of the tetraimide 3 with 2 mol monopyrone 7 to the bicycle 8 was carried out. © 1995 John Wiley & Sons, Inc. 相似文献
95.
Michael Klemm 《Journal of Geometry》1991,41(1-2):114-123
BOSE and CONNOR [2] proved that a symmetric regular divisible design with w classes of sizes g and joining numbers 1 and 2 must satisfy for every prime p the arithmetic condition (d1, (–1)sw)p(d2,(–l)tgw)p=1, where d1=k2–v2, d2= k–1 s=(w-1)(w-2)/2, t=(v-w)(v-w-1)/2 and (*,*) is the Hilbert symbol. We show that if in addition 1 2 and the design is fully symmetric divisible then (d1, (–1)s w)p=(d2, (–1)tgw)=1. Our assumption is by a result of CONNOR [5] fulfilled, if d1 and 1–2 are relatively prime. Thus, we can exclude parameters not accessible to the Bose-Connor-Theorem. Our result can be derived from a theorem of RAGHAVARAO [9], and we give the precise assumptions of this theorem. We also discuss arithmetic restrictions for divisible designs which satisfy diverse other rules for the intersection numbers and generalize a result of DEMBOWSKI [6; 2.1.11].Dedicated to Professor Benz on occasion of his sixtieth birthday 相似文献
96.
97.
98.
Preparation, Isolation, and Characterization of Mixed Thiocyanato(ethylenediamine)rhodium(III) Complexes The complexes Na[Rh(SCN)4(en)] and trans-[Rh(SCN)2(en)2]SCN are prepared for the first time. They are isolated from the mixture by column chromatography on aluminia and characterized by the spectra and the CHN analysis. 相似文献
99.
Ph(C2)CH2Cl and Ph(C2)'CO2Na [where (C2) = -C=C- or trans-CH=CH-, (C2)' = -C=C- or cis-CH=CH-] reacted in refluxing dimethylformamide to yield unsaturated esters Ph(C2)'CO2-CH2(C2)Ph and/or their intramolecular Diels-Alder cyclization products (cyclolignan lactones). It was found that modal selectivity for cyclization in DMF sometimes varies from that found previously with acetic anhydride as solvent. Two new parent tetrahydrocyclolignan lactones were synthesized. 相似文献
100.
By-products in the syntheses of 2-(1- and 2-naphthyl)pyridines by successive treatments of 1- and 2-bromonaphthalenes with (a) n-butyllithium in ether and (b) pyridine are identified as 5-butyl-2-(1-naphthyl)pyridine and, tentatively, 5-butyl-2-(2-naphthyl)pyridine, respectively. It is proposed that these by-products result from reaction of intermediate compounds 1-lithio-2-naphthyl-1,2-dihydropyridines and 1-bromobutane. 相似文献