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Bromo sulfone

If the reaction is run on the unsaturated bromo sulfones (RCH2CH=CHS02CH2-Br) (prepared by reaction of BrCH2S02Br with RCH2CH—CH2 followed by treatment with Et3N), the dienes (RCH=CHCH=CH2) are produced in moderate-to-good yields.The compound mesyltriflone (CF3SO2CH2SO2CH3) can be used as a synthon for the tetraion Successive alkylation (10-104) converts it to... [Pg.1342]

Taylor and Evans extended the substrate for the MIRB to other nucleophiles including methoxide, thiol, and amines in place of de Waard s sulfinate.26 For instance, Michael addition of benzylamine to bromo-vinylsulfone 27 gave the adduct as bromo-sulfone 28, which upon treatment with a base led to the Ramberg-Backlund reaction product 29 in 83% yield. [Pg.390]

Large ring heterocycles have also been synthesized using the Ramberg-BScklund reaction. Preparation of [2.2]-(2,6)pyridinopha-l-ene (80) from bromo-sulfone 79 is one example,52 and rrans-olefin 83 from sulfide 81 is another via the intermediacy of chloro-sulfone 82.53... [Pg.397]

Addition to Unsaturated Compounds. Benzenesulfonyl bromide undergoes radical-mediated addition to alkenes and alkynes. Addition to alkenes leads to bromo sulfones, which undergo dehydrobromination to give vinyl sulfones (eq 3). ... [Pg.26]

Scheme 3.12 Cross-couplings of a-bromo sulfonamides and a-bromo sulfones with arylzinc reagents. Scheme 3.12 Cross-couplings of a-bromo sulfonamides and a-bromo sulfones with arylzinc reagents.
This mixture is known as Quinoline Yellow A [8003-22-3] (Cl 47000) and is most widely used with polyester fibers (109). Upon sulfonation, the water-soluble Quinoline Yellow S or Acid Yellow 3 [8004-92-0] (Cl 47005) is obtained. This dye is used with wool and its aluminum salt as a pigment. Foron Yellow SE-3GL (Cl Disperse Yellow 64) is the 3-hydroxy-4-bromo derivative. Several other quinoline dyes are commercially available and find apphcations as biological stains and analytical reagents (110). [Pg.395]

Among anthraquiaoae dyes (see Dyes, anthraquinone). Acid Blue 78 [6424-75-5] C2 H25BrN20 S -Na, or Alizarin Pure Blue B, is a wool dye. Bromamine acid [116-81-4] (l-amiao-4-bromoanthraquiaoae-2-sulfonic acid), C24HgBrNO S, is a useful dye iatermediate. A number of bromo anthraquiaoae, pyrathroae, and benzanthrone dyes are known. [Pg.297]

A Methylanthrapyridone and Its Derivatives. 6-Bromo-3-methylanthrapyridone [81-85-6] (75) is an important iatermediate for manufacturiag dyes soluble ia organic solvents. These solvent dyes are prepared by replacing the bromine atom with various kiads of aromatic amines. 6-Bromo-3-methylanthrapyridone is prepared from 1-methyl amino-4-bromoanthra quin one (43) by acetylation with acetic anhydride followed by ring closure ia alkaU. The startiag material of this route is anthraquiaoae-l-sulfonic acid (16). [Pg.317]

Oxetane, 3,3-bis(trimethylaminomethyl)-methane sulfonate X-ray crystal structure, 7, 365 Oxetane, 3-bromo-synthesis, 7, 390 Oxetane, 2-t-butyl-3-methyl-synthesis, 7, 399 Oxetane, 2-chloro-reactions, 7, 390 Oxetane, 3-chloro-synthesis, 7, 390... [Pg.732]

Naphthoic acid has been prepared principally by the hydrolj sis of d-naphthonitriled the overall yields from (3-naph-thylamine, from sodinm-/3-naphthalene sulfonate, and from calcium d-naphthalene sulfonate being given as (approximately) 20 per cent, 21 per cent, and 50 per cent, respectively. The acid has been prepared also by the carbonation of the Grignard reagent from the less accessible /3-bromo derivative and. more recendy, from the readily available methyl ketone. ... [Pg.67]

Other direct methods for the sulfonation of the higher fatty acids are by the use of sulfur trioxide vapor or by the use of chlorosulfonic acid. Indirect methods are also available for the preparation of a-sulfo fatty acids and their salts from an a-bromo fatty acid made by the Hell-Volhard-Zelinsky reaction. The bromo compound may be converted directly to the sodium salt of a sulfonic acid through the Strecker reaction or may be converted to the mercaptan and oxidized to the sulfonate. Sulfonation of the lower fatty acids has been studied by Backer and co-workers. ... [Pg.86]

Only one of these methods, namely the reaction of halides with lithium aluminum deuteride, is a true displacement reaction, following the same course as the previously discussed displacement of sulfonate esters (section Vl-A). Thus, lithium aluminum deuteride treatment of 7a- and 7jS-bromo-3 -benzoyloxy-5a-cholestanes (195) and (196) gives the corresponding deuterium labeled cholestanols (197) and (198) respectively." ... [Pg.199]

The 2,2 -bis(phenylthiomethyl) dispiroketal (dispoke) derivative is cleaved by oxidation to the sulfone, followed by treatment with LiN(TMS)2. The related bromo and iodo derivatives are cleaved reductively with LDBB (lithium 4,4 -di- -butylbiphenylide) or by elimination with the P4- -butylphosphazene base and acid hydrolysis of the enol ether. The 2,2-diphenyl dispiroketal is cleaved with FeCl3 (CH2CI2, rt, overnight)." The dimethyl dispiroketal is cleaved with TFA, and the allyl derivative is cleaved by ozonolysis followed by elimination. ... [Pg.236]

Finally, certain 3-substituted compounds can be prepared by utilizing the - meta) directing powet (cf. Section IV,B) of some groups in the 2-position which afterward can be removed. 3-Nitrothiophene is prepared by nitration of 2-thiophenesulfonyl chloride and by removal of the sulfonic acid group of the 4-nitro-2-sulfonyl chloride formed with superheated steam. Another approach to 3-nitrothio-phene is to nitrate 2-cyanothiophene, separate the 4-nitro-2-cyano-thiophene from the 5-isomer, hydrolyze, and decarboxylate. A final method of preparation of 3-nitrothiophene is by simultaneous de-bromination and decarboxylation of 5-bromo-4-nitro-2-thiophene-carboxylic acid obtained through the nitration of methyl 5-bromo-2-thiophenecarboxylate. [Pg.43]

With weakly directing — I + M-substituents such as the halogens, the a-directing power of the ring sulfur dominates and substitution appears to occur exclusively in the 5-position. 2-Chloro-, 2-bromo-, and 2-iodo-thiophene are sulfonated both with chlorosulfonic aeid and in the 5-position. In the chlorination of chloro-... [Pg.47]

Quaternization of o-bromo-iv,iv-dimethyIbenzylamine with the p-toluene-sulfonate of ethanol affords bretylium tosylate (78), an antihypertensive agent acting by peripheral sympathetic blockade. [Pg.55]

Yosida et al. [41] found that p-t< rr-butylcalix[6]ar-ene can extract Cu from the alkaline-ammonia solution to the organic solvent. Nagasaki and Shinkai [42] described the synthesis of carboxyl, derivatives of calix-[n]arenes ( = 4 and 6) and their selective extraction capacity of transition metal cations from aqueous phase to the organic phase. Gutsche and Nam [43] have synthesized various substituted calix[n]arenes and examined the complexes of the p-bromo benzene sulfonate of p-(2-aminoethyl)calix[4]arene with Ni, Cu , Co-, and Fe. ... [Pg.342]


See other pages where Bromo sulfone is mentioned: [Pg.1031]    [Pg.1537]    [Pg.220]    [Pg.220]    [Pg.372]    [Pg.873]    [Pg.878]    [Pg.879]    [Pg.392]    [Pg.150]    [Pg.21]    [Pg.220]    [Pg.116]    [Pg.1031]    [Pg.1537]    [Pg.220]    [Pg.220]    [Pg.372]    [Pg.873]    [Pg.878]    [Pg.879]    [Pg.392]    [Pg.150]    [Pg.21]    [Pg.220]    [Pg.116]    [Pg.100]    [Pg.538]    [Pg.272]    [Pg.313]    [Pg.138]    [Pg.36]    [Pg.650]    [Pg.650]    [Pg.742]    [Pg.792]    [Pg.173]    [Pg.79]    [Pg.13]    [Pg.54]    [Pg.112]    [Pg.34]   
See also in sourсe #XX -- [ Pg.372 ]




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Sulfones a-bromo

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