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1.
The Synthesis of 6-substituted 2-Norbornanols The preparation of several 6-exo- and 6-endo-substituted 2-exo- and 2-endó-norbornanols and their p-toluenesulfonates is described.  相似文献   

2.
The Synthesis and Hydrolysis of 6endo-Substituted 2endo-Norbornyl p-Toluenesulfonates The hydrolysis products of the p-toluenesulfonates of several hitherto unknown 6endo-substituted 2endo-norbornanols have been determined.  相似文献   

3.
The isomers 6-methyl-2-propionyl- and 3-methyl-2-propionylbenzoic acid were synthesized and separated by DCC (droplet counter-current) chromatography. The crystal structure analyses showed that these compounds are hydroxylactones in the solid state.  相似文献   

4.
The Hydrolysis of 7-anti-Substituted 2-endo- and 2-exo-Norbornyl p-Toluenesulfonates The hydrolysis products of the title compounds have been determined. The preparation of the hitherto unknown solvolysis products is described.  相似文献   

5.
The Hydrolysis of 6 exo -Substituted 2 exo - and 2 endo -Norbornyl p -Toluenesulfonates. Norbornane Series. Part 3 Hydrolysis of the 6exo-substituted 2exo- and 2endo-norbornyl p-toluenesulfonates 1b - 1 and 2b - 1 , respectively, in 70% dioxane led to different amounts of the following products: Unrearranged 2exo-norbornanols 3 and norbornenes 5 , accompanied in somes cases by small amounts of the rearranged Rendo-epimers 4 and 6 and by norticyclenes 7 . When the 6exo-substituent was a nucleophilic group as in 1e - 1 and 2e - 1 , various amounts of tricyclic products were also formed by endo-cyclization. These results show that the 2exo- and 2endo-esters 1 and 2 , respectively, react by way of different intermediates. In cases where the 6exo-substituent was an n-electron donor, as in 1m - r and 2m - r , quantitative fragmentation to (3-cyclopentenyl)acetaldehyde (13) occurred.  相似文献   

6.
1. 4-Methylcinnoline on irradiation in ethers produces the photoproducts 2–6 by a 1.4 addition of the ethers. 2. Quinoxaline reacts with ethers to produce the quinoxalines 8, 12 and 13 by what appears superficially to be a substitution process. Reaction of 2,3-dimethylquinoxaline with tetrahydrofuran gives as the main product 16 by 1.2 addition, and 2-(t-butyl)-quinoxaline gives the dihydroquinoxaline derivatives 17a, b . Because of the known easy autoxidation of 1,2-dihydroquinoxaline we believe that the intermediate in the photolytic reaction of quinoxaline, yielding 8, 12 and 13 , is also the 1.2 addition product. 3. The mass-spectrometric behaviour of the cinnoline and quinoxaline derivatives has been discussed.  相似文献   

7.
8.
Synthesis and Crystal Structure of (PPh4)2Se6 (PPh4)2Se6 has been prepared by the reaction of selenium with K2Se2 in dimethylformamide solution in the presence of K3[Mn(CN)6] and PPh4Br, forming black crystal needles. According to the crystal structure determination the compound consists of PPh+4 ions and chainlike hexaselenide ions. Space group P6 , Z = 2,4683 Observed unique reflections, R = 0.066. Lattice dimensions at ?90°C: a = 951.0, b = 1094.8, c = 2137.4 pm, α = 82.66°, β = 83.36°, γ = 89.96°.  相似文献   

9.
10.
  • 1 The kinetics of the hydrolysis of three monochlorotriazine reactive dyes have been determined in alkaline buffer solutions at 60°, 80° and 98° (ionic strength I = 0.0625).
  • 2 The kinetic results as well as diffusion measurements in aqueous solution indicated that these dyes form aggregates at dye concentrations at 6 · 10?4, but practically not at 6·10?6 moles/l.
  • 3 The reaction order with respect to hydroxyl ions has been determined. The influence of general base concentration was negligible.
  相似文献   

11.
Claisen Rearrangement of 2-Propinyl (3-Pyridyl) and Allyl (3-Pyridyl) Ethers
  • 1 Verbindungen vom Typ 1 werden mit Ausnahme von 17 und 25 als Äther benannt. Der systematische Name von 1 ist: 3-(2-Propinyl)oxy-pyridin.
  • 2-Propinyl (3-pyridyl) ether ( 1 ), synthesized from the corresponding 3-pyridinol, was heated in DMF or decane at 208° in a sealed tube. In this way the furopyridines 2 and 3 were formed, and furthermore the pyranopyridine 4 if decane was used as solvent (Scheme 1). The same reactions took place with (2-methyl-3-pyridyl) 2-propinyl ether ( 14 ). In DMF only 15 , and in decane 16 as well as 15 were formed (Scheme 3). The rearrangement of the pyridine derivative 17 , which is substituted in both O-positions to the ether moiety, gave in both DMF and decane the diastereoisomeric tetracyclic compounds 18 and 19 . The same kind of reaction took place with 25 (Scheme 4). In the thermolysis of the allyl 3-pyridyl ether ( 27 ) cyclization was observed, too. The isolated product has the structure of the dihydrofuropyridine 28 (Scheme 6). The substituted allyl 3-pyridyl ether 30 reacted in the same way to the dihydrofuropyridine 31 (Scheme 6).  相似文献   

    12.
    The synthesis of a new (?)-Δ8-6a,10a-trans-tetrahydrocannabinol analogue, containing a N-methyl-3-propyl-pyrrolidin-3-yl side-chain, is reported.  相似文献   

    13.
    The syntheses of 2,7-dioxa-isotwistane ( 14 ), 2,7-dioxa-twistane ( 19 ), and some of their derivatives ( 6 – 13 and 15 – 18 ) are described. The twistane-skeleton was obtained by a molecular rearrangement starting from the iodo-iso-twistane compound 8 .  相似文献   

    14.
    A number of new [(3-amino-2,4,6-triiodo-benzoylamino)-phenyl- and -phenoxy]-alkanoic acids have been synthesized for evaluation as X-ray contrast agents. The toxicity, the bilitropism, and the urotropism of these compounds were determined.  相似文献   

    15.
    16.
    Synthesis of Novel (Phenylalkyl)amines for the Investigation of Structure–Activity Relationships. Part 21). 4‐Thio‐Substituted [2‐(2,5‐Dimethoxyphenyl)ethyl]amines (=2,5‐Dimethoxybenzeneethanamines) The 4‐substituted [2‐(2,5‐dimethoxyphenyl)ethyl]amines (=2,5‐dimethoxybenzeneethanamines) and its α‐methyl analogs are known to act as potent 5‐HT2A/C ligands, which have, depending on their 4‐substituent, agonistic or antagonistic character. Generally, compounds with a small lipophilic substituent typically are agonists and those with a larger lipophilic substituent predominantly antagonists or at least partial agonists. Since little is known about the transition and more information is needed about the structural requirements of the 4‐substituent to control the functional activity, 12 novel 4‐thio‐substituted [2‐(2,5‐dimethoxyphenyl)ethyl]amines were synthesized and spectroscopically characterized. Thus 2,5‐dimethoxybenzenethiol ( 7 ) was converted to the thioether derivatives 8a – l with several alkyl, fluoroalkyl, alkenyl, and benzyl halides. Subsequent Vilsmeier‐formylation afforded the benzaldehydes 9a – l , condensation with MeNO2 the nitroethenyl derivatives 10a – l , and reduction with AlH3 the desired (2‐phenylethyl)amines 11a – l .  相似文献   

    17.
    The photochemical reactions of different allyl aryl ethers (Scheme 3) were investigated in hydrocarbons (Chap. 3.1) and in alcoholic solvents (Chap. 3.2). The composition of the photoproducts depended very much on the nature of the solvent. Irradiation (3–95 h) of different methyl substituted allyl aryl ethers ( 1, 3, 5, 7 and 11 ) with a low pressure mercury lamp (λEmiss. = 254 nm; 6 or 15 Watt) under argon (quartz vessel) resulted in the formation of 2-, 3– and 4-substituted phenols, dienones and products of consecutive reactions (Tables 1–4 and 6). The results suggested that all products were formed by homolytic cleavage of the C? O bond in the singlet state of the ethers to intermediate radical-geminates (Scheme 5) followed by radical recombination of the two fragments. No products were formed by concerted processes (Table 5, Schemes 5 and 6). Upon irradiation of allyl aryl ethers lacking alkyl substituents at position 4 ( 1 and 5 ) in protic solvents, mainly 2- and 4-allylated phenols were obtained (Tables 1 and 4); 3-allylated phenols were formed only in small amounts (0.02%). However, in aromatic hydrocarbons or cyclohexane 3-allylated phenols were obtained from 1 , 5 and 11 in significant amounts (3–11%; Tables 1, 4 and 6). E.g., upon irradiation of allyl-2,6-dimethyl-2,4-cyclohexadien-1-one ( 6 ) besides 3- and 4-allyl-2, 6-dimethyl-phenol ( 23 and 24 ). Irradiation of 5 in methanol afforded 23 and 6 only in traces, whereas 24 was the main product.  相似文献   

    18.
    • 1 The kinetics of the hydrolysis of a dichlorotriazine reactive dye have been determined in aqueous buffer solutions at pH values between 8.50 and 13.47, at 24.0° and ionic strength I = 0.625.
    • 2 The reaction order with respect to the concentration of the dye and the hydroxyl ions is a complex function of the reaction conditions.
    • 3 Only in very dilute solutions the kinetics follow the mechanism postulated by Ackermann and Dussy [4].
    • 4 Several types of base catalysis can be detected, depending on conditions (pH, concentrations).
      相似文献   

    19.
    20.
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