Sulfoxides acidity

Aldicarb nitrile, see Aldicarb Aldicarb nitrile sulfone, see Aldicarb Aldicarb nitrile sulfoxide, see Aldicarb Aldicarb oxime, see Aldicarb Aldicarb oxime sulfone, see Aldicarb Aldicarb oxime sulfoxide, see Aldicarb Aldicarb sulfone, see Aldicarb Aldicarb sulfone acid, see Aldicarb Aldicarb sulfone alcohol, see Aldicarb Aldicarb sulfone aldehyde, see Aldicarb Aldicarb sulfone amide, see Aldicarb Aldicarb sulfone oxime, see Aldicarb Aldicarb sulfoxide, see Aldicarb Aldicarb sulfoxide acid, see Aldicarb Aldicarb sulfoxide alcohol, see Aldicarb Aldicarb sulfoxide aldehyde, see Aldicarb Aldicarb sulfoxide amide, see Aldicarb Aldicarb sulfoxide nitrile, see Aldicarb Aldicarb sulfoxide oxime, see Aldicarb Aldrin, see Dieldrin Aldrin diol, see Aldrin Alkyl hydroperoxides, see Acetaldehyde Allyl alcohol, see Allyl chloride, l,2-Dibromo-3-chloropropane, 1,2-Dichloropropane Allylbenzene, see Isopropylbenzene p-(2-Atnino-3-nitrophenyl)glucopyranoside, see 2-Nitroaniline Allyl chloride, see Allyl alcohol, l,2-Dibromo-3-chloropropane, 1,2-Dichloropropane 2-Aminobenzimidazole, see Benomvl... 

Rajagopal et al. (1984) used numerous compounds to develop a proposed pathway of degradation of aldicarb in soil. These compounds included aldicarb oxime, A-hydroxymethyl aldicarb, A-hydroxymethyl aldicarb sulfoxide, A-demethyl aldicarb sulfoxide, A-demethyl aldicarb sulfone, aldicarb sulfoxide, aldicarb sulfone, A-hydroxymethyl aldicarb sulfone, aldicarb oxime sulfone, aldicarb sulfone aldehyde, aldicarb sulfone alcohol, aldicarb nitrile sulfone, aldicarb sulfone amide, aldicarb sulfone acid, aldicarb oxime sulfoxide, aldicarb sulfoxide aldehyde, aldicarb sulfoxide alcohol, aldicarb nitrile sulfoxide, aldicarb sulfoxide amide, aldicarb sulfoxide acid, elemental sulfur, carbon dioxide, and water. Mineralization was more rapid in aerobic surface soils than in either aerobic or anaerobic subsurface soils. In surface soils (30 cm depth) under aerobic conditions, half-lives ranged from 20 to 361 d. In subsurface soils (20 and 183 cm depths), half-lives under aerobic and anaerobic conditions were 131-233 and 223-1,130 d, respectively (Ou et al, 1985). The reported half-lives in soil ranged from approximately 70 d (Jury et ah, 1987) to several months (Jones et al, 1986). Bromilow et al. (1980) reported the half-life for aldicarb in soil to be 9.9 d at 15 °C and pH 6.34-7.0. 

Scheme 3 Intramolecular Disulfide Formation by Dimethyl Sulfoxide/Acid 461...

Intramolecular Disulfide Formation with Dimethyl Sulfoxide/Acid... 

A further development of the DMSO/H+ method for oxidation of cysteine peptides led to the cysteine-sulfoxide acid-catalyzed intermolecular disulfide formation with a second S-unprotected or acid-labile protected cysteine component as shown in Scheme 19. 1471 The protonation of the sulfoxide by TfOH in the case of 5(0)-Mob or TFA in the case of 5(0)-Acm derivatives provides electrophilicity to the sulfur atom to allow attack by the second S-unprotected cysteine component (formed by the fast deprotection of the 5-Mob group with TfOH in presence of dimethylsulfide) to generate in a site-directed manner the interchain disulfide bond. Although extensive experience with this method has not been accumulated for interchain disulfide bridging, it has been successfully applied for intrachain site-directed disulfide bond formation in chicken calcitonin-gene-related peptide.1 79 ... 

Scheme 19 Site-Directed Interchain Disulfide Formation by the Cysteine-Sulfoxide/Acid Method 1471...

The first process, which was already in production in Ulverston (and, in part, in Montrose, Scotland), utilized the 2,2,2-trichloroethyl (TCE) group for die protection of die carboxyl group in die starting penicillin G sulfoxide acid for more detail of the need to change, see Chapter 7. 

Albright, J. D., Goldman, L. Dimethyl sulfoxide-acid anhydride mixtures. New reagent for oxidation of alcohols. J. Am. Chem. Soc. 1965, 87, 4214 216. 

Acetylenic Sulfoxide Acid T (°C) Isolated Products Isolated Yield... 

Attention has been paid to the polysulfonium salts as a new type of photochemical polymeric materials (121,122). Several kinds of poly(arylenesulfonium salt)s having methyl (40) propyl (41), and phenyl substituents (42, 43) including a novel class of polyelectrolites having triphenylsulfonio groups in the main chain (42,43) were synthesized in yield up to 100% by the sulfoxide-acid system reaction from the corresponding alkyl and aryl sulfoxide monomers (105,107,115,122). 

Utilization of simultaneous silyl protection of the sulfenic acid and of the carboxyl group allowed the development of a process for rearrangement of the penicillin sulfoxide acid (4) into a desacetoxycephem acid (46) in high yield (de Koning et al., 1975). 

In the presence of an acid anhydride, the corresponding thioester (e.g. 226), was formed in good yield (Hatfield et al., 1970). However, use of an acid (e.g., acetic) produced a rra/i -acylate, acetate 227 (Cooper and Jose, 1970 Suarato et al., 1978). Rearrangement of the penicillin sulfoxide acid (228) resulted in involvement of the carboxylic acid in an intramolecular fashion to produce the lactone (229) (R. D. G. Cooper, 1970, unpublished results). 

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