Aryl tosylates

Enolate arylation has also been extended to aryl tosylates. The preferred catalyst includes a very bulky biphenyl phosphine D.179... 

NiCl2[P(c-C6Hn)3]2 is an effective catalyst for coupling aryl tosylates with arylboronic... 

Several metal cross-coupling reactions have been applied to pyrazoles. C-H Arylation of aryl tosylates or chlorides could be achieved with a ruthenium catalyst at the C-2 phenyl position of... 

Organic molten salts such as tris-n-butyl-dodecylphosphonium halides (melting point below 40°C) have been used as reaction media for nucleophilic aromatic substitution of aryl tosylates by halide ions (Fry and Pienta, 1985). 

Primary /3-aryl tosylates have also been shown to undergo solvolysis by two distinct pathways—aryl- and solvent-assisted.32 Tertiary /J-aryl tosylates, however, ionize to a stable carbocation and seem to require no assistance in isomerization.33... 

A ruthenium catalyst derived from a secondary diaminophosphine oxide has been used successfully in the arylation of C-H bonds by aryl tosylates.41... 

General Procedure for Coupling of Aryl Tosylates According to Buchwald and Gelman [48]... 

Scheme 5.23 The /MCD-mediated aza-MBH reaction of aryl tosyl aldimines with acrolein and acrylonitrile. EWG = electron-withdrawing group.

Table 5.16 The 119a-mediated aza-MBH reaction of aryl tosylated imines with MVK and EVK.

Just as deprotonation of NH3 gives the sequence NH3 —> NH2 —> NH2 N3-, alkyl or aryl amines give the NHR- and NR2 species of the last section and finally NR2- which is isoelectronic with O2. There is, however, a difference in that imido ligands can be either linear or bent (see below). In imido compounds the R groups can be H, alkyl, aryl, tosylate, CR2OH, CH2CH=CH2, 1-pyrolylimido, etc. 

Hartwig reported the first amination of an aryl tosylate with an aliphatic amine. Utilizing electron-rich ferrocene-based ligand 20, the coupling with hexylamine shown below proceeded in 83 % isolated yield, Eq. (119) [72]. 

Hartwig reported the first arylation of aniline using an aryl tosylate. The reaction was catalyzed by a 13/Pd-catalyst, Eq. (126). Using a bulky base and elevated temperatures, the desired product was obtained in 78% yield [72]. 

Magnesium in methanol has been used to convert sulfonate esters to the parent alcohol. Likewise, CeCls H2O—Nal in acetonitrile converted aryl tosylates to the parent phenol derivative. " ... 

FIGURE 8. X-phos, a derivative of ligand 11 in Figure 5, synthesized for amination of unactivated aryl tosylates... 

Reaction of diarylamines with aryl nonaflates as part of the synthesis of discrete oligomeric triarylamines has also been reported104. Only one paper reports the palladium-catalyzed reactions of diarylamines with aryl tosylates this reaction was conducted with X-phos 31 (Figure 8) as the ligand in mixed solvents of 5 1 toluene t-butanol98. 

Hi. Reactions with aryl tosylates. The reaction of aniline with an activated aryl tosylate has been catalyzed by a combination of palladium and DfBPF 19 (Figure 6) to produce a high yield of diarylamine under relatively mild conditions79. The reaction of unactivated aryl tosylates with anilines has been more recently reported using catalysts containing X-phos 31 (Figure 8) in the presence of 5% phenylboronic acid98. 

From 2-bromobenzaldehyde, isoindolinones and 3-alkylphthalides are obtained by reaction with amines " (imines ) and 1,3-dicarbonyl compounds, respectively. Alkyl aroates are similarly accessible from aryl tosylates, but the scope is very limited, as only 4-acetylphenyl tosylate furnishes acceptable yields. ... 

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