Diimide source

Namely, if the double bond was saturated ( ) simultaneously when it formed, the retardation of the development of conjugated polymer structure might be expected. We chose the reduction with diimide (NH=NH) for the saturation of double bond. Thus, p-toluenesulfonyl hydrazide (PSH) was used which acts as a diimide source under the condition (130-150°C) of PVC-processing. 

N,N - Bis(trimethylsilyl)sulfur(rV) diimide Me3SiN=S=NSiMc3 is an especially versatile source of the N=S=N functionality in the formation of both acyclic and cyclic S-N compounds. It is conveniently prepared by the reaction of NaN(SiMc3)2 and thionyl chloride (Eq. 2.5). 

Diimide geometry energies Calculated B. Munsch, Dissertation, Strasbourg (1971). Same source as geometry. 

The reagent can be prepared in situ, by the copper-catalyzed oxidation of hydrazine. Hydrogen peroxide or oxygen are often the oxidants. The acid-catalyzed decomposition of potassium azodicarboylate provides a useful source of diimide ... 

Dinitro-p-azostilbene or Azobis-(9-nitrostilbene, called in Beil Bis-[4 -nitro-stilbenyl-(4)]-diimid or [4 -Nitro-stilben]-<4azo4>-[4,-nitro- stilben], (OjN KAf- CH CH— C6H4-N N-C6H4-CH CH-CsH4(N01) yel-red Crystspmp 263°. It is listed in Beil 16, 84 without reference to its source was not found in CA through 1956... 

Thiadiazoles. An acyclic NCCN system in which the NC links may be sp, sp2, or sp3 hybridized reacts with sulfur monochloride or sulfur dichloride to form the appropriate 1,2,5-thiadiazole <1968AHC(9)107, CHEC-111(5.09.9.1.5)545>. Aliphatic 1,2-diamines can be converted into 1,2,5-thiadiazoles using various sulfur sources such as tetrasulfur tetranitride, disulfur dichloride, sulfur dichloride, thionyl chloride, and V(V-ditosylsulfur diimide. Thus, l,2,5-thiadiazole-3,4-dicarbonitrile 555 is prepared from diaminomaleonitrile 554 using neat excess thionyl chloride (Scheme 250) <1995SR299>. 

While it is true that the photochemical decomposition will produce a very liot NH, the surroundings are at —200° C. We may then expect stabilization of the NH and Reaction Q may be an important source of diimide it might be expected, too, that at —200° C. Reactions R l and R 2 would not be important until warming up occurred. 

The experiments revealed firstly that the diimide function alone is not the source of the autocatalysis. This was established by control experiments with the diimide methyl ester (11) (Figure 8). This molecule did not catalyze the reaction of (12) with (4) rather, inhibition resulted, probably as a consequence of its sequestering the aminoadenosine in an unproductive complex. Additional experiments with (22) (Figure 15), which competes only poorly for adenosines, further supported the conclusion that an imide is an ineffective catalyst. 

Complexation of nitrogen by Cu " " has been used to advantage in several cases. The selective hydrolysis of a-aminodiesters is guided by chelation to nitrogen and activation of the vicinal ester group (eq 4). Cycloreversions of 2-azanorbomenes to give primary amines are catalyzed efficiently by copper sulfate (eq 5). Copper sulfate (or other Cu " " sources) facilitates the preparation of diimide from hydrazine by complexation with nitrogen. See also copper(II) acetate. 

Alkene Reduction. 2,4,6-Triisopropylbenzenesulfonyl hydrazide (TPSH) undergoes solvent-dependent thermal degradation into diazene (diimide) between 35 and 65 °C, resulting in the in situ reduction of alkenes and other double bonds in good to excellent yields. TPSH remains one of the best sources of diazene, and addition of amine bases increases the rate of both diazene formation and hydrogenation. It is the most reactive of the common arenesulfonylhydrazides, being 380 and 24 times more reactive than /j-toluenesulfonylhydrazide and mesitylenesulfonylhy-drazide, respectively, under base-catalyzed conditions. ... 

A multi-component reaction of a terminal alkyne, sulfur, electrophile (E-X) and carbodiimides, R R CH-N=C=N-R, produces 1,2-dihydrothiopyrimidines and 2,3-dihydropyrimidinthiones (43, R" derived from alkyne, E = H, alkyl). The expected N=C cleavage of the diimide is accompanied by an unexpected C(5p )-H cleavage, such that the carbodiimide acts as sources of H -I- R R -C-N -I- C=N-R , with subsequent reorganization to give products. 

In any Cl plasma, ions of both polarities, positive and negative, are formed simultaneously, e.g., [M-j-H]" and [M-H]" ions, and it is just a matter of the polarity of the acceleration voltage which ions are extracted from the ion source [71]. Thus, negative-ion chemical ionization (NICI) [72] mass spectra are readily obtained when one of the following processes occurs i) dissociation (deprotonation) of acidic analytes such as carboxylic acids, diimides, or phenols, ii) nucleophilic addition (anion attachment), or Hi) ion-pair formation [73-76] ... 

The ribofuranosyl-oxazolidine thione(6) has been used as a source of a-ribofuranosyl imidazole derivatives leading to purine and 2-azapurine a-nucleosides. D-Arabinose or D-ribose reacts with cyanamide to yield isomeric 2-amino-l,2-oxazolines (7), which are useful intermediates for nucleoside synthesis.The P-N ylide (8) has been used to prepare tetrazole nucleosides by conversion to the diimide (9) with isocyanate and subsequent azide cyclo addition.Conversely, glycosyl azides undergo cyclo-... 

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