Sulfonamide alcohol

A wide range of linker groups are currently used with SynPhase crowns. They accommodate formation of the following functional groups upon cleavage carboxylic acids, primary and secondary amides, sulfonamides, alcohols, phenols, amines, anilines, anilides, hydroxymates, aldehydes, ketones, and thiols. 

The synthesis of unique seven-membered ring sultams has been reported, by an intramolecular oxa-Michael addition reaction from vinyl sulfonamides 248 via a one-step or two-step method, both of which give similar yields of sultams, 249 (13T2369).The intramolecular oxa-Michael reaction was initiated by either TBS-deprotection (with TBAF) to form alkoxide intermediates (Method A), or by removal of the protecting group by HCl to give vinyl sulfonamide alcohols which, upon reaction with NaH, the oxa-Michael reaction is initiated (Method B). 

Carhon nucleophiles of pXa 10-20 have heen most studied and often work hest with these substrates (eq 1), hut enamines, cyclopentadiene anions, enolates (eq 2), organotin, -thaUium, -zinc, -aluminum, -lithium, and -zirconiums, as weU as Grignards (eq 3) and horates, also add to r-allylpaUadium complexes. Heteroatom nucleophiles also add successfully these include amines (eq 4), amides, azides, magnesium amides, sulfonamides, alcohols, acids (eq 5), nitrites, sulhnic acids, thiols, phosphines, and phosphites. Limited use of transition metal nucleophiles is also known. ... 

Although hydroamination of allenes can be easily achieved with group 4 and group 5 metal catalysts, the stereoselectivity of these systems is rather limited. Several attempts to perform asymmetric hydroamination/cyclization of aminoallenes employing chiral aminoalcohols [260, 261] and sulfonamide alcohols [262] as chiral proligands for titanium- and tantalum-based catalyst systems have produced vinyl pyrrolidines with low selectivities only. While the titanium catalysts were... 

Several sulfonamides (142), Rj = p-H2NS02CeH4, have been obtained by condensing the corresponding thiosemicarbazide (141), R, = p-H2NSO2C6H4, with a-halocarbonyl compounds (396, 466) in alcohol solution. 

Acetoiicetyliition Reactions. The best known and commercially most important reaction of diketene is the aceto acetylation of nucleophiles to give derivatives of acetoacetic acid (Fig. 2) (1,5,6). A wide variety of substances with acidic hydrogens can be acetoacetylated. This includes alcohols, amines, phenols, thiols, carboxyHc acids, amides, ureas, thioureas, urethanes, and sulfonamides. Where more than one functional group is present, ring closure often follows aceto acetylation, giving access to a variety of heterocycHc compounds. These reactions often require catalysts in the form of tertiary amines, acids, and mercury salts. Acetoacetate esters and acetoacetamides are the most important industrial intermediates prepared from diketene. 

For example, Day-Glo HM Series toners come ia a range of colors suitable for flexographic and gravure inks of the solvent-base type. The Radiant GF Series and Lawter HVT Series are also suitable for this type of apphcation (see Table 2). Generally, these toners are of the formaldehyde—sulfonamide type and requite oxygenated solvents, primarily alcohol—ester blends, for proper solution. For appHcations such as flexographic printing on film, these materials are modified with other resias such as nitrocellulose or polyamides ia the finished ink. 

Sulfonamide groups can be introduced into phthalocyanines to make them soluble in alcohols and glycol ethers. Their main appHcations are transparent paints, flexo and gravure printing inks, wood stains, plastics, and ballpoint inks. This includes products Hke Solvent Blue 24 (Cl 74380),... 

The amino group is readily dia2oti2ed in aqueous solution, and this reaction forms a basis for the assay of sulfas. Aldehydes also react to form anils, and the yellow product formed with 4-(dimethylamino)hen2a1dehyde can be used for detection in thiu-layer and paper chromatography. Chromatographic retention values have been deterrnined in a number of thiu layer systems, and have been used as an expression of the lipophilic character of sulfonamides (23). These values have corresponded well with Hansch lipophilic parameters determined in an isobutyl alcohol—water system. 

Me3Si)2NH, Me3SiCl, Pyr, 20°, 5 min, 100% yield. ROH is a carbohydrate. Hexamethyldisilazane (HMDS) is one of the most common sily-lating agents and readily silylates alcohols, acids, amines, thiols, phenols, hydroxamic acids, amides, thioamides, sulfonamides, phosphoric amides, phosphites, hydrazines, and enolizable ketones. It works best in the presence of a catalyst such as X-NH-Y, where at least one of the group X or Y is electron-withdrawing. ... 

In terms of cost, the effectiveness of the catalytic cycle in the ring closure makes this process economical in palladium. The first three steps in the reaction sequence -- ring opening of an epoxide by a Grignard reagent, converison of an alcohol to an amine with inversion, and sulfonamide formation from the amine — are all standard synthetic processes. 

Having observed that (i) the zinc carbenoid must be formed prior to addition of the alcohol or sulfonamide and (ii) that the zinc alkoxide should be preformed in order to obtain high selectivity, the importance of the zinc sulfonamide could be assessed (Fig. 3.14). In this sub-set, flask A contains the preformed zinc alkoxide, flask B contains the promoter solution and flask C contains the preformed zinc carbenoid. In sub-protocol Ilia, flasks A and C are combined prior to addi-... 

Although the previous protocol suggests it is not necessary to deprotonate the sulfonamide prior to exposure to the zinc carbenoid, a experimentally simpler procedure can be envisioned wherein the alcohol and promoter are deprotonated in a single flask (Fig. 3.15). In protocol IV, the alcohol and promoter are combined in flask A and are treated with diethylzinc, thus forming the zinc alkoxide and zinc sulfonamide. In sub-protocol IVa, this solution is transferred to flask C which contains the zinc carbenoid. Sub-protocol IVb represents the reversed addition order. Sub-protocol IVa is not only found to be the superior protocol in this sub-set, it is found to out-perform all of the previous protocols Despite the persistence of the induction period, a large rate enhancement over the uncatalyzed process is observed. This considerable rate enhancement also translates to a reduction in the overall reaction time when compared to sub-protocols la and Ilia. Selectivity rises... 

Another point for structural diversification is the sulfonamide group. Imai had already shown that a wide variety of groups could be introduced at this position to optimize the reaction. Since a wide variety of sulfonyl chlorides are commercially available, a number of different types of groups could be examined (Scheme 3.34). Testing of a variety of aryl and alkyl groups on the 1,2-cyclohexanediamine backbone demonstrates that the simple methanesulfonamide 122 is clearly superior or equal to many other analogs in the cyclopropanation of cinnamyl alcohol (Table 3.11). Another concern which was directly addressed by this survey was the question of catalyst solubility. 

Chiral boron(III) complexes can catalyze the cycloaddition reaction of glyoxy-lates with Danishefsky s diene (Scheme 4.18) [27]. Two classes of chiral boron catalyst were tested, the / -amino alcohol-derived complex 18 and bis-sulfonamide complexes. The former catalyst gave the best results for the reaction of methyl glyoxylate 4b with diene 2a the cycloaddition product 6b was isolated in 69% yield and 94% ee, while the chiral bis-sulfonamide boron complex resulted in only... 

Additions of oxygen and nitrogen nucleophiles to vinyloxiranes can be achieved with Pd(0) catalysis [103, 104]. Acetate, silanols, amines, sulfonamides, and azide have been used as nucleophiles, and the stereochemical outcome of these additions, where applicable, is normally the result of two consecutive SN2 reactions. This is demonstrated by the additions of NaNHTs to vinylepoxides 29 and 30, affording syn- and anti-amino alcohols 31 and 32, respectively, in good yields and with high diastereoselectivities (Scheme 9.22) [105]. 

Conjugate additions of alkylcopper- boron trifluoride to enoates of sulfonamide-shielded alcohols (6 and 7) quite generally proceeded with >99% de and >90% yield30. The following general trend has emerged from the reactions of 6 and 7. 

Optically active bicyclo[2.2,2]octanes can be obtained via diastercoselective MIMIRC reaction of lithium dienolates and a,/ -unsaturated esters of various chiral alcohols. Good yields (70-90%), high endo selectivities (> 95%) and diastereomeric ratios that depend on the auxiliary alcohol are found in these additions. The highest diastereomeric ratio reached was 18 82 using a camphor derived sulfonamide. The diastereomeric ratio could be improved (up to 9 91) by titanium(IV) chloride catalyzed addition of the corresponding silylenolates with the chiral a,/J-unsaturated esters358. 

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