Sulfur Protocol

European satellites followed the Soviet leadership and joined the treaty (Darst 2001 Levy 1993). All communist countries except Poland ratified the First Sulfur Protocol (1985), which required 30% reduction of 1980 levels of SOj( emissions, but did little in terms of implementation during the 1980s beyond measures that addressed local air pollution. In 1988, CEE countries became parties to the Protocol on Nitrogen Oxides (NO, ), which required stabilization of NO, at 1987 levels by 1994. 

The 1994 Protocol on Further Reduction of Sulphur Emissions (Second Sulfur Protocol)... 

Source Second Sulfur Protocol for SO2 2000 ceilings, Gothenberg Multi-Pollutant Protocol for SO2 and NO 2010 ceilings Convention on Long-Range Transboundary Air Pollution 2005 for emissions data (accessed via http //webdab.emep.int/). Estonia has no commitments under the Second Sulfur Protocol or the Gothenberg Multi-Pollutant Protocol and is not included in the table. 

Since the beginning of the transition period in 1989, aggregated acidifying emissions in CEE declined steadily (Figure 8.1). By 2000, most CEE countries over-complied with their emission ceilings set by the 1994 Sulfur protocol, which they argued back in 1994 would be costly and close to impossible to achieve (Table 8.1). Data as of 2002 also indicates that most CEE countries are either already compliant, or on a steady path toward com-... 

As a result of domestic activism, Czechoslovakia adopted a Clean Air Act in 1991, which required considerable emission reductions and technical standards of desulfurization from all power plant facilities to be implemented by 1998. By the time of the negotiations of the Second Sulfur Protocol in 1994, the implementation of the 1991 Clean Air Act was already under way in the successor states of Czechoslovakia—the Czech Republic and Slovakia—contributing to significant declines in both sulfur and nitrogen emissions (Eigure 8.2). It is thus no surprise that the Czech Republic as well as Slovakia committed to high levels of emission reductions under the Second Sulfur Protocol, as their domestic legislation demanded similar if not stricter standards. 

The impact of the LRTAP process during the 1980s was lessened by the fact that the United States did not sign the sulfur protocols under this convention and also by the fact that the first LRTAP nitrogen protocol, which both Canada and the United States signed, did not require the United States to adopt significant new measures. 

Reactions between A -(l-chloroalkyl)pyridinium chlorides 33 and amino acids in organic solvents have a low synthetic value because of the low solubility of the amine partner. A special protocol has been designed and tested in order to circumvent this drawback. Soon after the preparation of the salt, an aqueous solution of the amino acid was introduced in the reaction medium and the two-phase system obtained was heated under reflux for several hours. However, this was not too successful because sulfur dioxide, evolved during the preparation of the salt, was converted into sulfite that acted as an 5-nucleophile. As a result, A -(l-sulfonatoalkyl)pyridinium betaines such as 53 were obtained (Section IV,B,3) (97BSB383). To avoid the formation of such betaines, the salts 33 were isolated and reacted with an aqueous solution of L-cysteine (80) to afford thiazolidine-4-carboxylic acids hydrochlorides 81 (60-80% yields). 

The application of double Fischer indolization has been demonstrated to provide larger amounts of the indolocarbazole 4 from the treatment of the hisphenylhydra-zone 151 with aqueous sulfuric acid (63JCS2504). A considerably more efficient protocol has been devised by Robinson, who obtained 4 in 35% yield on treatment of 1,4-cyclohexanedione bisphenylhydrazone (151) in a mixture of acetic acid and sulfuric acid (63JCS3097). In spite of many recent developments, this is still the method of choice for the preparation of the parent system 4 as the starting materials are cheap and readily available. Cyclization of 151 in ethanol-water containing... 

The oxidation of heteroatoms and, in particular, the conversion of sulfides to asymmetric sulfoxides has continued to be a highly active field in biocatalysis. In particular, the diverse biotransformations at sulfur have received the majority of attention in the area of enzyme-mediated heteroatom oxidation. This is particularly due to the versatile applicability of sulfoxides as chiral auxiliaries in a variety of transformations coupled with facile protocols for the ultimate removal [187]. 

Perspectives on the field of NMR of iron-sulfur proteins are those common to the broader field of NMR of diamagnetic proteins, with a particular need for high technical skills. For some applications, new experiments/protocols tailored for the study of paramagnetic systems such as those described here will probably have to be designed and... 

X-ray crystallographic analyses of the structures show that the P-S bond distance vary over one-half of an Angstrom (2.36-2.88 A). The derivatives were generated using procedures similar to those utilized to form pentaoxyphosphoranes with P-N bonds, that is (i) the oxidation of sulfur containing cyclic chlorophosphines with a quinone or (ii) treatment of phosphites with the sulfur-containing diol in presence of N-chlorodiisopropylamine. Two typical examples of these synthetic protocols are shown in Scheme 10. 

P 68] No detailed experimental protocol was given [61, 62,142,143]. Two reactant streams, the solution of the reactant in hexane and concentrated sulfuric acid, were fed separately in a specially designed micro reactor by pumping action. There, a bilayer was formed initially, potentially decomposed to a dispersion, and led to rapid mass transfer between the phases. From this point, temperature was controlled by counter-flow heat exchange between the reaction channel and surrounding heat-transfer channel. The reaction was typically carried out at temperatures from 0 to 50 °C and using residence times of only a few seconds. If needed, a delay loop of... 

Corrosive wastes are acidic or alkaline (basic) wastes which can readily corrode or dissolve flesh, metal, or other materials. They are also among the most common hazardous wastestreams. Waste sulfuric acid from automotive batteries is an example of a corrosive waste. U.S. EPA uses two criteria to identify corrosive hazardous wastes. The first is a pH test. Aqueous wastes with a pH greater than or equal to 12.5, or less than or equal to 2 are corrosive under U.S. EPA s rules. A waste may also be corrosive if it has the ability to corrode steel in a specific U.S. EPA-approved test protocol. 

More than 90% of the nickel and cobalt in laterite ores (1.0-1.6% nickel) can readily be leached by sulfuric acid at >240 °C, typically producing large volumes of relatively dilute leach solution containing 3-6 gL-1 of nickel and around 40 gL-1 H2S04.98 In addition to nickel and cobalt these leach solutions contain Al, Cr, Ca, Cu, Fe, Mg, Mn, Na, Si, and Zn.89 The design of reagents and protocols for the separation and concentration of metal values in these streams has depended heavily on differences in the coordination chemistry of the components. 

A palladium-catalyzed protocol for carbon-sulfur bond formation between an aryl triflate and para-methoxybenzylthiol was introduced by Macmillan and Anderson (Scheme 6.66) [138], Using palladium(II) acetate as a palladium source and 2,2 -bis(diphenylphosphino)-l,l -binaphthyl (BINAP) as a ligand, microwave heating of the two starting materials in N,N-dimethylformamide at 150 °C for 20 min in the presence of triethylamine base led to the formation of the desired sulfide in 85% yield. 

Another frequently used multicomponent reaction is the Kindler thioamide synthesis (the condensation of an aldehyde, an amine, and sulfur). The Kappe group has described a microwave-assisted protocol utilizing a diverse selection of 13 aldehyde and 12 amine precursors in the construction of a representative 34-member library of substituted thioamides (Scheme 6.114) [226]. The three-component con-... 

In the context of the preparation of a library of pyrazole-based cyclooxygenase II (COX-II) inhibitors, the Organ group has described the microwave-assisted decarboxylation of a pyrazole carboxylic ester with 20% sulfuric acid (Scheme 6.160 a) [49]. While the conventional protocol (reflux, 100 °C) required 96 h to provide a yield of 86%, full conversion could be achieved within 5 min at 200 °C under micro-wave heating, leading to an 88% isolated product yield. 

Scheme 6.186) [347]. The condensation of O-allylic and O-propargylic salicylalde-hydes with a-amino esters was carried out either in the absence of a solvent or - if both components were solids - in a minimal volume of xylene. All reactions performed under microwave conditions rapidly proceeded to completion within a few minutes and typically provided higher yields compared to the corresponding thermal protocols. In the case of intramolecular alkene cycloadditions, mixtures of hexa-hydrochromeno[4,3-b]pyrrole diastereoisomers were obtained, whereas transformations involving alkyne tethers provided chromeno[4,3-b]pyrroles directly after in situ oxidation with elemental sulfur (Scheme 6.186). Independent work by Pospisil and Potacek involved very similar transformations under strictly solvent-free conditions [348]. 

Sodium cyanoborohydride [123], sodium triacetoxyborohydride [124] or NaBH4 coupled with sulfuric acid [125] are common agents used for the reductive amination of carbonyl compounds. These reagents either generate waste or involve the use of corrosive acids. The environmentally friendlier procedures developed by Varma and coworkers have been extended to a solvent-free reductive amination protocol for carbonyl compounds using moist montmorillonite K 10 day supported sodium borohydride that is facilitated by microwave irradiation (Scheme 6.39) [126]. 

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