Chloride benzenesulfenyl, reaction

A variety of other activating systems have been employed for the promotion of sulfoxide-based glycosylation reactions, but none have been studied to the same extent as the triflic-anhydride-mediated reaction [86]. One of the most potent activators, benzenesulfenyl triflate, a by-product of the activation with triflic anhydride, has been shown to bring about rapid conversion of sulfoxides into glycosyl triflates [280]. Unfortunately, this reagent is unstable and has to be prepared in situ from silver triflate and benzenesulfenyl chloride. 

It is noteworthy that 108 reacts in AcOH with benzenesulfenyl chloride to give a 1 1 mixture of the sulfur analogues of 138 and 140, but when the reaction is carried out in the presence of LiClC>4 a complex mixture of at least five products was detected. From this comparison the authors suggest that areneselenenylation is much less affected by the solvent than arenesulfenylation, and if the reaction profiles for the two product-forming processes are assumed to be similar, the difference in product distributions can be interpreted in terms of a more efficient bridging ability of selenium than that of sulfur. In the addition of selenenyl derivatives, the solvent-dependent product distribution has also... 

The reaction proceeds smoothly and gives 326 in 43% yield. The stereochemistry of the addition is exo with respect to the norbomene moiety and in line with the usual cycloaddition behavior of quadricyclane [358]. The norbomene double bond in 326 is easily accessible by electrophiles, and, for example, the anti-addition of benzenesulfenyl chloride proceeds quantitatively at room temperature (Scheme 4.66). 

Reaction with allene sulfoxides.1 Allenic sulfoxides are desulfurized by reaction with methyllithium. An example is the transformation shown in equation (I). The propynylcarbinol 1 is treated with benzenesulfenyl chloride to form the allene 2,... 

Tricyclenes. Benzenesulfenyl chloride reacts with 5-mcthylene-2-norbornene (1) to form the tricyclcnc derivative 2. This reaction was used to synthesize tricyclo-e a-santalol (3)1 and cyclosativene (4).2... 

N-Arylamidines act as 1,5-dinucleophiles towards sulfur dichloride, N-sulfinyltosylamide and bis(N-tosyl)sulfur diimide. The products are 1,2,4-benzothiadiazines (Scheme 14) (73ZOR2038, 68LA(715)223), and in the case of sulfur dichloride, chlorination of the aromatic ring also occurs. 1,2,4-Benzothiadiazines can also be prepared from N-arylamidines by reaction with sulfenyl chlorides or disulfides in the presence of NCS. Thus N-phenylben-zamidine and benzenesulfenyl chloride give the 1,2,4-benzothiadiazine (182) (78CC1049). 

Toluenesulfenyl chloride has been prepared by the action of chlorine on a solution of -toluenethiol or />-tolyl disulfide in anhydrous carbon tetrachloride.2,3 Benzenesulfenyl chloride has also been obtained by the interaction of hydrogen chloride and N,N-diethylbenzenesulfenamide 4 and by reaction of benzenethiol with N-chlorosuccinimide.6 A comprehensive review dealing with sulfenyl halides and related compounds is available.6... 

Another useful cyclization results in the stereoselective synthesis of -lactams from thiiranium ions derived from a, -unsaturated amides. Unsaturamd amides are treated with benzenesulfenyl chloride and the product is subsequently treated with base under phase transfer conditions. The reaction legeiMiates a thiiranium ion in the presence of amide anion, which then tyclizes to form -lactams. The regiochemistry of the alkene aMtion determines the eventual stereochemical outcome e.g. cis alkenes produce c(5- -lactams Scheme 2). The yields of the cyclization products are quite sensitive to the amide-protecting group which was enqtloyed. With 4-anisyl amide the yield is modoate (73%), but wdth 4-nitr henyl amide the yield is excellent (97%), suggesting that the amide must be deprotonated before cyclization can occur. 

Benzenesulfenyl chloride can convm unsaturated adds to lactones. The unsatuiated add (7) is treated with benzenesulfenyl chloride, followed by Raney nickel, to afford the 7-lactone (8) in excdlent overall yield (equation 5). Another acid (9) has been lactonized to produce the spiro-p-lactone (10) whidi rearranges on silica gel to 7-lactone (11 equation 6). 6-Lactones have been also prqrared using diis rq>-proach. An additional advantage of this approach is that the phenyl sulfide moiety can be manipulated into a variety of functional groups to facilitate cyclization. in suirunary, successfiil cyclization reactions... 

In the stereoselective total synthesis of ( )-14-deoxyisoamijiol by G. Majetich et al., the last step was the epimerization of the C2 secondary allylic alcohol functionality. The Mitsunobu reaction resulted only in a poor yield (30%) of the inverted product, so the well-established sulfoxide-sulfenate rearrangement was utilized. The allyic alcohol was first treated with benzenesulfenyl chloride, which afforded the thermodynamically more stable epimeric sulfenate ester via an allylic sulfoxide intermediate. The addition of trimethyl phosphite shifted the equilibrium to the right by consuming the desired epimeric sulfenate ester and produced the natural product. 

Sulfenyl chlorides undergo the Friedel-Crafts reaction with suitable aromatic compounds to produce the corresponding sulfides thus, benzenesulfenyl chloride condenses with anisole to give p-methoxyphenyl phenylsulfide (Scheme 41). 

It was initially reported that 1-methylcyclopropene underwent cis addition of benzenesulfenyl chloride to give a mixture of 1 -chloro-1 -methyl-2-phenylsulfanylcyclopropane (6) and 1 -chloro-2-methyl-2-phenylsulfanylcyclopropane (7). ° However, a later report indicated that the reaction gave a cisitrans mixture of the 6 regioisomer. Addition to 3,3-dimethylcyclopropene was reported to occur in a trans manner to give... 

Analogously benzenesulfenyl chloride was added to 5-methylenenorborn-2-ene in di-chloromethane at 0°C to give 2-chloromethyl-5-phenylsulfanyltricyclo[2.2.1.0 ]heptane (28) in 85% yield.This reaction has been used in the synthesis of tricyclo-cfcu-santol, a minor constituent of East Indian Santalwood oil Santalum album... 

The skeleton can be synthesized from myrcene (7) (brominative cyclization was mentioned in Vol. 4, p. 534, Ref. 583), either by reaction with benzenesulfenyl chloride (giving 719), or by epoxidation (to 720) before cyclizing with SnCl4 or trifluoroacetic acid. The cyclized products 721 (R = OCOCF3 or Cl, R = OH or SPh) were converted to the boll-weevil pheromone 722 (R... 

Sun then went on and provided a series of examples of his new reaction, involving coupling to primary, secondary, and tertiary alcohols as set out in Table 3 [27,35], The obvious advantage of this new method is that it eliminates the need to oxidize thioglycosides to sulfoxides. The disadvantage is that the reagent has to be freshly prepared in sim from AgOTf and benzenesulfenyl chloride which, itself, has only limited shelf life. 

A similar transposition can be applied to saturated ketones. For example, a ketone is treated with a vinyl organometallic reagent to generate a derivative of an aUylic alcohol. Reaction with benzenesulfenyl chloride then gives an aUylic sulfoxide by means of a [2,3] sigmatropic rearrangement. The remain-... 

Enolates react with sulfenyl halides to give an a-alkylthio ketone. As shown for cyclohexanone, reaction with LDA followed benzenesulfenyl chloride (PhSCl) produced phenylthio derivative 109. The proton adjacent to both the carbonyl and the sulfur (the a-proton) was more acidic and it was deprotonated with potassium hydride, forming the enolate, and alkylation with iodobutane gave a 91% yield of 110. As mentioned in Chapter 2, the sulfide moiety can be oxidized to a sulfoxide and thermally eliminated (syn elimination, sec. 2.9.C.v) to give an alkene. 9 Similar methodology can be applied to selenides, R—Se—R. O... 

The observation that the ti level of 104 is the HOMO is in line with the observation that electrophiles react with the double bond. Thus, reaction of 104 with such reagents as bromine chlorosulfonylisocyanate or benzenesulfenyl chlorid occurs by initial rr bond attack. In the case of 106 and its congeners, a marked preference for electrophilic attack by at the edge bicyclobutane bonds has been found ... 

---