Modem Methods

Internal ynones and alkynes have been frequently used as starting materials for the synthesis of quinoline compounds. Ynones can act as Michael acceptors with various nucleophiles, affording intermediate enones, which are readily cyclized to quinolines.  

Mono-substituted anilines bearing an internal alkyne can be cyclized to quinolines either by metal-mediated hydroarylation of alkynes or through an eleetrophile-mediated Friedel-Craft type reaction.  

Several metals have been reported of being able to hydroaiylate alkynes as in the examples shown below. Thus, di-substituted-propargyl anilines can be cyclized either in the presence of copper(I) chloride at reflux or by a mixture of palladium acetate and trifluoroacetic acid.  

Intramolecular or intermolecular Heck-type reactions were also used in the synthesis of poly-substituted quinoline compounds. Palladium-catalyzed reaction between vinyl or aryl halides and ortAo-allyl-substituted-A -tosyl-anilides produces dihydroquinolines in an intermolecular fashion, where reaction of acrylates intramolecularly affords 4-quinolones. ° °  

A modification of the Negishi cross-coupling has also been used for a wide range of nitrogen heterocycles. In accordance to that, the zinc reagent derived from protected iodoaniline can be treacted with a-substituted carbethoxy vinyl-triflates to produce quinolin-2-ones.  

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K. Bolton, W. Hase, and G, Peslherbe, in Modem methods for multi-dimensional dynamics computations in chemistry, D. Thompson, ed.. World Scientific, Singapore, 1998, pp, 143-189,... 

Modem methods of peptide sequencing follow a strategy similar to that used to sequence insulin but are automated and can be carried out on a small scale A key feature is repetitive N terminal identification using the Edman degradation... 

H. F. Linskens and J. F. Jackson, Wine Analysis, Vol. 6 in Modem Methods of Plant Analysis, Springer Vedag, Berlin, 1988. 

Aqueous ammonia and acryUc esters give tertiary amino esters, which form the corresponding amide upon ammonolysis (34). Modem methods of molecular quantum modelling have been appHed to the reaction pathway and energetics for several nucleophiles in these Michael additions (35,36). 

H. Heloma and E. Kovene, "A Modem Method for Determining the Stabihty and Stabilizers in Sohd Gun PropeUants," in Proceedings of the 6th... 

R. H. Marijnissen, Paintings, Genuine, Fraud, Fake Modem Methods of Examining Paintings, Elsevier, Bmssels, 1985. 

T. Cairns and J. Sherma, eds.. Emerging Strategiesfor Pesticide Analysis, CRC Press, Boca Raton, Fla., 1992, 368 pp. From the series Modem Methods of Pesticide Analysis, presents survey of improvements in extraction and cleanup, detailed descriptions of alternative analytical methods, latest appHcations, and up-to-date references. 

Another method of separating petrolatum from residua is by centrifuge dewaxing. In this process, the reduced cmde oil is dissolved in naphtha and chilled to —18° C or lower, which causes the wax to separate. The mixture is then fed to a battery of centrifuges where the wax is separated from the Hquid. However, the centrifuge method has been largely displaced by solvent dewaxing methods as well as more modem methods of wax removal. Similar use is... 

When a sample of ca 100 g has been obtained, a representative sample for use in size characterization equipment must then be taken. Some of the more modem methods of size characterization require as Htde as 1 mg of powder, thus obtaining a representative sample can be quite difficult. If the powder flows weU and does not contain too many fines, a device known as the spinning riffler (Fig. 4c) can be used. A spinning riffler consists of a series of cups that rotate under the powder supply. The time of one rotation divided into the time of total powder flow should be as large a number as possible. Although this device has been shown to be very efficient, problems can be encountered on very small (1 mg) samples, and the powder must be processed several times. Moreover, in order to avoid cross-contamination, cleanup after each of the sampling processes can be quite difficult. Furthermore, if the powder is cohesive and does not flow weU, the equipment is not easy to use. A siUca flow agent can be added to the powder to enable the powder to flow... 

The appHcation of modem methods of analyses such as gc, low ionization voltage mass spectrometry, high pressure Hquid chromatography (hplc), and nmr has greatly increased knowledge of coal-tar composition without materially altering the quaHtative picture. 

For any control valve design be sure to use one of the modem methods, such as that given here, that takes into account such things as control valve pressure recovery factors and gas transition to incompressible flow at critical pressure drop. 

Sabadilla Seeds. Processes for the isolation of the total alkaloids and separation of the components have been published by Wright and Luff, by Bosetti and by G. Merck. The more modem methods used by Poethke, Saito, Seiferle et al., Jacobs and Craig, and others for the alkaloids of white and green hellebores (see below) could no doubt also be used to advantage for sabadilla seed. A test for galenical preparations of sabadilla has been devised by Ramstad depending on the presence of chelidonie acid in the seed. ... 

Modem Methods To Prepare Monofluoro-aliphatic Compounds Shafts, C M, Sheppard, W A Org ReuLlions 21, 125-146 386... 

Modem Methods for the Introduction of Fluonne into Organic Molecules An Approach to Compounds with Altered Chemical and Biological Activities... 

Development of classical and modem methods for the synthesis of arylpyrroles 98ZOR967, 98ZOR1767. 

Furthermore, LandS s theory only represents a first-order approximation, and the L and S quantum numbers only behave as good quantum numbers when spin-orbit coupling is neglected. It is interesting to note that the most modem method for establishing the atomic ground state and its configuration is neither chemical nor spectroscopic in the usual sense of the word but makes use of atomic beam techniques (38). 

Modem methods for the manuf and storage of expl materials, which include many exotic chemicals, fuels, and propints, allow less space for a given quantity of expl material than previously permitted. Such concns of expls increase the possibility of the propagation of accidental explosions (one accidental explosion causing the detonation of other expl materials). It was evident that a requirement for more accurate design techniques had become essential. Ref 3 describes a rational design method to provide the required structural protection. It presents methods of design for protective construction... 

For dicussions of reactions 10-104 and 10-105, see House, H.O. Modem Synthetic Reactions, 2nd ed. W. A. Benjamin NY, 1972, pp. 492, 586 Carrathers, W. Some Modem Methods of Organic Synthesis, 3rd ed. Cambridge University Press Cambridge,... 

Carruthers, Some Modem Methods of Organic Synthesis , 3rd ed., Cambridge University Press, Cambridge, 1986. 

Shevchenko MA, Taran PH, Marchenko PV. 1982. Modem methods of purifying water from pesticides. Soviet J Water Chem Technol 4 53-71. 

Jeffrey, S.W., Structural relationships between algal chlorophylls, in Phytoplankton Pigments in Oceanography Guidelines to Modem Methods, Jeffrey, S.W., Mantoura, R.F.C. and Wright, S.W., Eds., UNESCO, Paris, 1997, 566. 

Francis [26] has recently described some modem methods for element determinations, including the oxygen flask technique and the determinations of C, H, O, N (Kjeldahl), halogens, S, P and F (ion-selective electrode). 

C. Vandecasteele and C.B. Block, Modem Methods for Trace Element Determination, J. Wiley Sons, Ltd, Chichester (1993). 

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