Transformation treatment

Analyzers with Fourier Transform Treatment of the Signal... 

FT-ICR and the Orbitrap belong to this group. In these analyzers the m/z values of the ions are not directly measured, but they are obtained by Fourier transform treatment of the signal (Figure 2.12). 

The ester groups in five-membered cyclic nitronates were successfully subjected to different transformations. Treatment of nitronates containing the methoxycarbonyl groups at positions 3 and 5 with butylamine at 20°C afforded the corresponding diamides (237b) (Scheme 3.119, Eq. 2). Their yields depend dramatically on the nature of the substituent R (further transformations of these products are shown in Scheme 3.109). 

Scheme 47 contains syntheses of [l,2,4]triazolo[4,3- ]pyridazine derivatives by ring closure of the triazole moiety. Kozhevnikov et al. reported <2005MC31> an interesting ring transformation treatment of the... 

Table XV. Regression Accuracy with Various Transformation Treatments of Data. Chlorothalonil Data Set.

Although cedranoid sesquiterpenes have earlier been synthesized, a renewed interest in alternative methods for elaborating these frameworks has arisen. The stereo-specific approach to (x-cedrene and a-patchoulene skeletons designed by Deslong-champs and summarized in Scheme XLIII is a case in point Beginning with the Stork-Clarke intermediate 559, the tetracyclic cyclopropyl diketone 560 was elaborated via a series of standard transformations. Treatment of 560 with three equivalents of sodium methoxide in methanol at room temperature for 20 min... 

W. H. McCrea, Proc. Roy. Soc. Lond. A 240, p. 447 (1957) (gives general properties in tensor form of superpotentials and their gauge transformations treatment more concise than Nisbet s, but entirely equivalent when translated into ordinary spacetime coordinates). 

The sulfide-based linker 1.32 (89), obtained from commercial thio-PEG-PS resin and chloropyrimidine, is activated to nucleophilic substitution via oxidation with perbenzoic acid after multistep SP transformations treatment with amines then releases pure 2-aminopyrimidines in solution. Other nucleophiles should be suitable for the modular release of this and other heterocyclic S-supported nuclei. 

Heating a mixture of diastereomeric oxaziridine 44 at 70 °C for 3h resulted in formation of pyrrole ester 46 as the only product <2002TA437>. Hydroxy imine 45 was suggested as an intermediate with transformation. Treatment with... 

The success of the Wolff-Kishner and related C==0 to CH2 transformations (see Chapter 1.14, this volume) attests to the efficiency of the diazene decomposition route applied to the reductive deamination of primary amines, this requires methods which transform RNH2 into RN=NH, which corresponds to an amination-oxidation sequence. Several one- or two-step processes have been described which carry out this transformation. Treatment of amino acids in alkaline solution with excess hydroxylamine-O-sul-fonic acid (HOS) gave moderate yields of deamination product, as exemplified by the dipeptide case shown in equation (23). 

The oxidative coupling/cyclization reaction is the intramolecular union of two arenes with formal loss of H2 promoted by a Pd(II) species (typically Pd(OAc)2). In an early example of this transformation, treatment of diphenylamines 1 with Pd(OAc)2 in acetic acid yielded carbazoles 2 [8]. The role of acetic acid in such oxidative cyclization processes is to protonate one of the acetate ligands, which affords a more electrophilic... 

These reactivities encouraged the investigation of reduction into NH3 and spectacular results were obtained with triphosphine-borane Fe complexes. Various V-bound Fe complexes 65 relevant to the catalytic reduction of into NH were prepared. Most significant are the protonation of the [FeJ-NH complex into [Fe]-NHj and the reductive displacement of NH by N, which are the toal steps proposed to account for the fixation/reduction of at Fe (Scheme 25). This stoichiometric reaction sequence was adapted into a catalytic transformation. Treatment of the anionic complex 65d with excess and KCj at -78°C results in NHj production. Under these conditions, up to 7 NH3 molecules were generated per Fe complex and more than 40% of the furnished protons were delivered to Nj. The borane moiety plays a major role in this process, being capable of accommodating the various [FelN H, )] species involved in the catalytic cycle due to its versatile coordination properties. This is further supported by the inability of the related triphosphine-silyl complex to promote the reduction of Nj under similar conditions. 

L.M. Shao, B. Tang, X.G. Shao, G.W. Zhao and S.T. Liu, Wavelet Transform Treatment of Noise in High Performance Liquid Chromatography, Chine.se Journal of Analytical Chemistry 25 (1997), 15-18 (in Chinese). 

DoleschaU and Seres described a novel base-catalyzed isoxazole-oxazole ring transformation. Treatment of ethyl 5-hydroxy-3-(5-methylisoxazol-4-yl)isoxazole-4-carboxylate 115 with KOrBu/DMF produced ethyl 4-cyano-5-methyloxazol-2-yl acetate 120 in 82% yield. Mechanistically, the authors proposed a base-catalyzed Beckmann rearrangement of 115 via the intermediate ketenimine 118 to account for isolation of 120 (Scheme 1.32). The structure of 120 was confirmed by saponification and decarboxylation to 4-cyano-2,5-dimethyloxazole 121. The generality of this novel rearrangement has not yet been defined. 

The combination of TMSCl and triethylamine provides another choice of dehydrating agent. For example, stirring a mixture of 1-nitronaphthyl tolyl sulfone, TMSCl, and triethylamine in DMF at rt for 4 days provides the corresponding anthranil in 72% yield (eq 50). In a similar transformation, treatment of substituted ort/io-nitroarylethanes with TMSCl and triethylamine in DMF results in formation of 1-hydroxyindoles as the dehydra-tion/cycUzation producL ... 

Che has reported the tandem hydroamination/hydroarylation of aromatic amines wirh terminal alkynes to form dihydroquinolines in which 1 equiv of aniline combines with 2 equiv of alkyne [23]. For example, reaction of 3-methoxyanilme with pheny-lacetylene (5 equiv) and a catalytic 1 1 mixture of the gold(I) N-heterocydic carbene complex (IPr)AuCl (IPr= l,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidine) and AgOTf at 150 °C under microwave irradiation led to isolation of dihydroquinoline 21 in 82 % yield (Eq. (11.15)). Alternatively, reaction of o-acetylaniline with pheny-lacetylene catalyzed by a mixture of (IPr)AuCl and AgOTf at 150 °C led to isolation of the quinoline derivative 22 in 93% yield via incorporation of a single equivalent of alkyne (Eq. (11.16)). Arcadi has reported the gold(IlI)-catalyzed hydroamination/ hydroarylation of 2-alkynylanilines with a,p-enones to form C3-alkyl indoles [24]. As an example of this transformation, treatment of 2-(phenylethynyl)aniline with 4-phenyl-3-buten-2-one and a catalytic amount of sodium tetrachloroaurate dihydrate in ethanol at 30°C formed 1,2,3-trisubstituted indole 23 in 88% yield (Eq. (11.17)). 

Building on the earlier work of Hashmi [15], Liu has reported the gold-catalyzed cycloisomerization and oxidative cyclization of (Z)-enynols [16,17]. As an example of the former transformation, treatment of the tetraphenyl enynol 7 with a catalytic amount of AuCh in dichloromethane at room temperature led to isolation of... 

A single report on enantioselective [1,2]-Wittig rearrangements was published by Tomooka and Nakai in 1999. A chiral bis-oxazoline ligand was employed to facilitate asymmetric lithiation/rearrangement of dibenzyl ether and benzyI(propargyl) ether derivatives with enantioselectivities ranging from 40-65% ee. In a representative transformation, treatment of 61 with -BuLi and bis-oxazoline 62 led to the formation of 63 in 86% yield and 60% ee. 

Bromoenals and 1,3-dicarbonyl compounds undergo a controlled and divergent NHC (28)-catalyzed oxidative transformation treatment with an external oxidant provides 2ff-pyran-2-ones, while in the absence of an external oxidant, chiral 3,4-dihydro-2ff-pyran-2-ones are obtained in moderate to good yields and with good enantioselectivity (Scheme 46)... 

Yield strength vs Rockwell C hardness curve fit from 13 and 25 mm (112 and 1.0 in.) plate of Transage 129 alloy after STA (solution heat treat and age) and STIT (solution heat treat and isothermally transform) treatments. 

Theoretical aspects related to the above problems have been elaborated and discussed in detail in the Ab initio theory of complex electronic ground state of superconductors , published recently [52a, b]. The main theoretical point is a generalization of the BOA by sequence of canonical - base function transformations. This formalism is equivalent to our original one, based on quasi-particle transformation treatment [53]. The final electronic wave function is explicitly dependent on nuclear coordinates Q and nuclear momenta P. Emerging new quasiparticles, i.e. nonadiabatic fermions, are explicitly dependent on nuclear dynamics. As a result, the effect of nuclear dynamics can be calculated as corrections to the clamped nuclei ground state electronic energy, the one-particle spectrum and the two-particle term, i.e. to the electron correlation energy ... 

Although this explanation may not be very convincing, we do not have any alternative. Presence of the intermediate 90 is necessary for this transformation. Treatment of aldehyde 85 with the same mild phase transfer catalysis reagent, but without the presence of 86, was completely ineffective the aldehyde remained unchanged. 

The practical use of chromium(II) chloride in organic synthesis was begun by Hiyama and Nozaki in 1976. They used anhydrous chromium(II) chloride for the reduction of allylic halides to get allylic chromium reagents [47]. Since then, useful C-C bond formation reactions between organic halides and carbonyl compounds, which were mediated by chromium(II) salt have been developed. The most important features of these reactions were chemoselectivity and stereoselectivity. In these transformations, treatment of organic halides with chromium(II) salt was considered to afford the intermediary organochromium compounds although these compounds have not been isolated. As described in the previous section, reduction of gem-dihalides with chromium(II) salt may afford gem-dichromium species. 

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