Veri-Green process

Pigments contained in canned green beans processed by conventional methods and by the Veri-Green process were determined... 

As for solid acids, it should be noted that there are already very green processes using acid catalysts in solution (not solid) as exemplified later. It is also noted in these examples that the greermess very much depends on the selectivity of the reaction and the separation of products and catalysts. Therefore, we must consider carefully for each case the trade-off relationships between risk and benefit and between one risk and other risks. Several methods at different levels may be necessary for the evaluation. For ordinary chemists and chemical engineers involved in R D, an easily applicable method is desirable. 

Commercially available stable green metallo-chlorophyU colorants could be produced and in 1984 Segner et al. patented the process to preserve the green color in canned vegetables under the Veri-Green trade name. Some years later, the formation and stability of these complexes were found to be dependent on the type of metal, pH, ionic concentration, temperature, and chlorophyll species — which could explain the unpredictable color changes observed in the beginning. ... 

Amination of aromatic nitro compounds is a very important process in both industry and laboratory. A simple synthesis of 4-aminodiphenyl amine (4-ADPA) has been achieved by utilizing a nucleophilic aromatic substitution. 4-ADPA is a key intermediate in the rubber chemical family of antioxidants. By means of a nucleophibc attack of the anilide anion on a nitrobenzene, a o-complex is formed first, which is then converted into 4-nitrosodiphenylamine and 4-nitrodiphenylamine by intra- and intermolecular oxidation. Catalytic hydrogenation finally affords 4-ADPA. Azobenzene, which is formed as a by-product, can be hydrogenated to aniline and thus recycled into the process. Switching this new atom-economy route allows for a dramatic reduction of chemical waste (Scheme 9.9).73 The United States Environmental Protection Agency gave the Green Chemistry Award for this process in 1998.74... 

The reactions can be carried out in aqueous solutions or biphasic mixtures of the substrates with no additional solvent, in the presence of NaOAc (pH s 11.5) at 100 °C. At this pH the resting state of the catalyst is probably the dinuclear species depicted on Scheme 8.1, which falls apart upon coordination of the substrate alcohol. In this respect the catalyst system as very similar to that for the oxidation of terminal olefins [10,11]. Good results were obtained with 30 bar of air, however, an 8 % O2/N2 mixture can also be used, which further improves the safety of the process. Recycling of the aqueous catalyst solution is possible and is especially easy in case of biphasic reaction mixtures. Taking all these features, this Pd-catalyzed oxidation of alcohols is a green process, indeed. 

A patented process for the production of green notes applying bakers yeast for in situ reduction of enzymatically produced aldehydes [67, 68] has been called into question regarding the effective production of (Z)-3-hexenol. According to Gatfield s report [69] the isomerisation of (Z)-3-hexenol to (E)-2-hexenal is a very fast process. The latter undergoes facile conversion to hexanol. Beside this, baker s yeast can add activated acetaldehyde to ( )-2-hexenal, forming 4-octen-2,3-diol. 

For X-ray excitable phosphors, the intensifier effect is tested as a measure of the luminescence yield. A very simple process uses the exposure of blue- or green-sensitive films. The phosphor is excited by X rays in a cell covered with a light-sensitive film. The blackening of the film is measured with a densitometer and, for given excitation conditions, is a measure of the efficiency of the phosphor. 

In this review, we have shown the major advances in the growing field of cascade chemistry that have led to regio-, chemo-, and stereoselective formation of several new carbon-carbon and carbon-heteroatom bonds in a stepwise economical fashion by using transition metal-catalyzed reactions. These approaches have already allowed very impressive and rapid construction of unnatural and natural polycyclic compounds of very high molecular complexity. These initial achievements should stimulate the synthetic community to pursue further works notably to develop more efficient and selective strategies that involve new generations of versatile catalysts. Next endeavors will have to focus on green processes as well as asymmetric catalysis. 

The ACTIS process described above is a typical example of low-pressure plasma polymerization or LCVD, which is an ultimate green process with no effluent in the practical sense. Microwave plasma is used for plasma polymerization of acetylene. ACTIS process, as an example of LCVD, has an ideal combination of unique advantages in (1) very high reaction yield (monomer to coating), (2) no effluent from the process, (3) no reactor wall contamination because the reactor wall is the substrate surface, and (4) very short reaction time. However, whether such an ideal LCVD process is an industrially viable practice is a totally different issue. 

Transition metal-catalyzed conversion of carbon monoxide (CO) and carbon dioxide (CO2) into high-value organic compounds is a very important process in synthetic organic chemistry, industrial chemistry and green or sustainable chemistry [1], Among the transition metals, ruthenium shows very characteristic catalytic performance. 

Very simply, the "Sea Of Green" process begins by cutting a clone from the mother plant, and then placing it in the proper medium. The rooted clones are grown for a desired time, and are then forced to flower or mature to a certain stage by manipulating their photoperiod. 

Electrosynthetic methods using sacrificial anodes are very promising. In particular, when both cathode and anode participate in the synthetic product, the process is quite clean or a green process. Moreover, it is very simple to manage a simple DC source connected to an undivided cell is sufficient. 

As we said, spectroscopic transitions to or from the 5f 6d(t2g) manifold of Cs2ZrCl6 U have not yet been observed experimentally however, states belonging to this manifold might be directly involved in very interesting processes observed in this material the green-to-blue upconversion [86,87], as we will discuss immediately. 

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