Unusual production

The formation of 2-(t-butyl)-2-trimethylsilyl-2//-thiopyran has recently been reported from 1-substituted 1,3-butadienes with /-BuCSSiMe3 (92MI1) (see Scheme 2). An unusual product with proposed structure 47b has been reported (84JOC5143) from benzothiopyrone 46 on reaction with sec-butyl lithium (46 - 47a — 47b, Scheme 3) on the basis of spectroscopic data. 6-Methylthio-2//-thiopyran was isolated after the flash vacuum thermolysis of more complex starting precursors (93TL2605). 

TPEs offer a combination of strength and elasticity as well as exceptional processing versatility. They present creative designers with endless new and unusual product opportunities. More than hundreds of major different groups of TPEs are produced worldwide, with new grades continually being introduced to meet different electrical, chemical, radiation, wear, swell, and other requirements (Tables 6-23 and 6-24). 

In searching for earlier precursors of helminthosporal the culture medium was examined daily up to 5 days. The composition showed little change after the appearance of activity, although the total amount increased. The only unusual product was anthraquinone found in the first 2 days growth. 

As might be expected, bacteria have been isolated from the plants that prodnce flnoroacetate, and these include an unidentified Pseudomonas sp. (Goldman 1965), a strain of Burkholderia Pseudomonas) cepacia from Dichapetalum cymosum (Meyer et al. 1990), and a strain of Morax-ella sp. (Kawasaki et al. 1981). In addition, fluoroacetate is an unusual product of microbial metabolism ... 

Depending on the reaction conditions, either one or both of the amino hydrogens can be removed in these reactions, and occasionally more unusual products, such as the tetranuclear ethylzinc/ethoxyzinc/2,6-diisopropylphe-nylamido complex 76, Figure 40, were isolated. 

No unusual products were formed with allylsilanes. Under similar conditions, allylsilanes made only 1,3-disubstituted propanes, and pro-penylsilanes were recovered if excess allylsilane was used. 

Wafers are an unusual product. They are often incorrectly included with biscuits, possibly because they are both made from soft wheat flour. Wafers, unlike biscuits, are a low fat, low sugar product. They normally consist almost entirely of flour. There is a very wide difference between the various sorts of wafers. Some wafers are made to serve with ice cream others are made to covered in chocolate and sold as confectionery. 

Oxidation of (alkenylthio)thiophenecarboxaldehyde oxime 350 (R = allyl) by NaOCl gives the nitrile oxide, which cyclizes to thieno[2,3-h]thiocino[4,5-c] isoxazole 351. However, isomeric 350 (R = isopropenyl), under the same conditions, is converted to the unusual product, thieno 2,3-/ thiocin 352. In both reactions, cyclodimerization products of nitrile oxides are also obtained. Structures of compounds 350 (R = isopropenyl) and 352 have been studied by X-ray diffraction analysis (411). 

These unusual products as well as adducts 109 and 106 may be attributed to the persistence of alkoxyamidyls they are isoelectronic with nitroxyl radicals and have significant delocalisation onto oxygen and hence, thermodynamic stability. The ESR... 

Much of the early work in this field invoked cationic homoaromaticity to account for the tremendous rate enhancement and unusual product... 

Dove Beauty Bar was developed by Lever Brothers Co., a subsidiary of Unilever in the United States, in the 1950 s. It has had an unusual product lifecycle in that it had a minor share of the U.S. soap market for over 25 years, after which it suddenly underwent a major expansion of market share, becoming the largest selling cleansing bar in the U.S. (as measured by dollar sales) [1,2],... 

Bamberger, Padova, and Ormerod reported in 1926 an interesting but incomplete study of several unusual products obtained from 5-amino-2,3-diaryl-l,2,3,4-tetrazolium salts (400). Recently this topic has been the subject of a detailed study by I. S. Smith, and the existence of several derivatives of meso-ionic l,2,3,4-tetrazol-5-imines (399) has now been firmly established. Comparison of Smith s recent results with the earlier results of Bamberger et alP is instructive. 

Anomalous isomerizations have been noted during the photolytic and thermal rearrangements of 3-acyl-2-methoxy-3//-azepines (2 R -acyl, R2 = OMe) and 3-acyl-3H- azepin-2-ones (69T5217). Irradiation in methanol solution produces mixtures of 3-azabicyclo[4.1.0]hepta-2,4-dienes (28 R1==acyl and H, R2 = OMe, R3 = H) (or -4-ene-2-ones) and 3-phenacylpyridines (or pyridones), albeit in poor yields. Detailed, but tentative, arguments involving azanorcaradiene and/or diradical intermediates are presented to explain the formation of these unusual products. 

In modern terms, one can begin to understand such processes only on the basis of the manner in which the simple reactant molecules combine with the metal atom of the catalyst, for the reactants must become bound to these species in order to respond so profoundly to the influence of the metal compounds. In recent years the isolation and characterization of a wide variety of organic derivatives of metal carbonyls have substantially improved the understanding of these processes (8, 9, 89). Some of these new compounds appear to be intermediates in previously discovered catalytic processes, while others may be utilized to obtain new and unusual products from such systems. One of the first types of intermediates to be isolated from systems of this class is exemplified by the substance... 

The electronegativity of an atom can vary in response to the partial charge induced hy substituent atoms or groups. For example, methyl iodide hydrolyzes as expected for alkyl halides, hut trifiuoromethyl iodide gives unusual products ... 

In the case of enaminoketone (77) and /j-benzoquinone, there are two parallel reactions in the /3-position of the enamine 77 and in the 8-position of the tautomeric dienamine 77a [93MC40 94KFZ(2)36]. The first pathway (common in the Nenitzescu reaction) gives a dibenzofuran derivative (78), the second affords an unusual product—a jpiro[benzofuran-3,l cyclohexene] derivative (79). The likely pathways are indicated. The... 

HNMR data have been used to determine the structure of certain unusual products obtained in the reaction of chlorohydroxypyrimido[4,5-c]pyridazines with phosphorus oxychloride and N,N-dimethylaniline (71CPB1849). NMR has also been used in the structure... 

Rh(C6Fg)Cl] 2, has also been reported 78), and an unusual product resulting from vicinal defluorination of this diene is discussed in Section III,G. 

Schmidt reaction of tetralone 114 gave, in addition to the expected isomeric benzazepinones, an unusual product of further ring expansion the eight-membered cyclic urea 115 (86JHC975). Cartier and co-workers treated the E-homovincamone derivative 116 with thionyl chloride to isolate 117 and 118 as major and minor products, respectively (76BSF1962). 

In 1996, Indian workers reported the formation of a most unusual product from the thermolysis of a highly substituted aryl azide (S.V. Eswaran, H.Y. Neela, S. Ramakumar and M.A. Viswamitra, J. Heterocyclic Chem., 33,1333-1337 (1996)). Thus, heating of the azide 1 in chlorobenzene for 4 hours at 130°C followed by removal of the solvent by distillation under reduced pressure and chromatography of the residue on silica gel gave the product 2 in 19% yield. The structure of 2 was established by X-ray analysis, but no mechanism was suggested for its formation. 

The formation of these unusual products was explained by the following two complex mechanisms, formation of 123-125 as depicted in Scheme 14 while formation of 126 as depicted in Scheme 15. 

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