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PRODUCT INFORMATIONProduct: PS-TrisamineChemical Name: Tris-(2-aminoethy1)aminepolystyreneCapacity: 3 - 4 mmoOg (based on benzoylchloride uptake)Resin wpe: 1 % crosslinked Poly(styrene-codivinylbenzene)Application: Scavenging acid chlorides, sulfonylchlorides, isocyanates, and other electrophileswpical Scavenging Conditions: 3 - 6 equivrelative to acid chloride, 1 - 4 h, 20 " C. If an additionalresin-bound base is present: 1.5 - 3 equivCompatible Solvents: CH2C12 ( 7 mL/g),THF (6Wg), DMF (5.2 mug) and other swellingsolventsRecommended Agitation: Gentle magneticstirring, swirling or overhead stirring for largeresin quantities (>5 g)1 part# Quantity 1Representative Procedure:Acid Chloride ScavengingReaction: The applicationamide synthesis was testedchloride (1.5 equiv, 0.60 mol) with benzylarnine(44 yL, 0.40 mmol) in the presence ofpyridine (97 pL, 1.2 mmol) in 2 mL of CH,C12 for1 h at RT.PS-Trisarnine is an arnine functional resin for theremoval of excess electrophilic reagents during thequenching and purification of reaction mixtures.' PS-Trisamine resin has a scavenging capacity of 3.0 - 4.0mrnol/g based on reaction with an excess of benzoy! -chloride. Scavenging of common electrophiles typicallyrequires a 3 - 6 equiv of PS-Trisarnine and occurswith 0.5 - 3 h at room temperature.The scope of PS-Trisamine as a scavenger for electrophilicreagents was investigated using 4-chlorobenzoylchloride, 2-phenylbutyryl chloride and 2,Gdimethoxybenzoyl chloride as a series of acid chlorideswith decreasing reactivity. Acid chlorides werecompletely scavenged in 0.5 h using 3.5 equivalentsPS-Trisamine (Table 2).The presence of a tertiarybase, e.g. PS-DIEA or PS-NMM, reduces the amount ofPS-Trisarnine required in the reaction by removing thehydrogen chloride formed. In addition to acid chlorides,benzenesulfonyl chloride and 4-methoxyphenylisocyanate were effectively scavenged in 0.5 h.TABLE 2. Comparative Scavenging ofElectrophiles in Dichloromethane for 0.5 hElectrophile4-Chlorobenioyl chloride2-Phenylbutyryl chloride2,GDimethoxybenzoyl chloride4-rnethoxyphenyl isocyanateBenzenesulfonyl chloridePS-Trisamine(equivI13.53.53.5241) Relative to electrophile, no additional base presentScavenged I100References1. Booth, R. J.; Hodges J. C. JAm. Chem. Soc, 1997,113,4882.Reaction Workub: 6 equiv of PS-Trisamine, relativeto excess acid chloride, was added to thereaction mixture and agitated for 3 h. The resinwas removed by fdtration and washed 3 x withCH,Cl, .The fdtrate was concentrated to affordthe desired amide. This procedure was used toprepare benzyl2,G.dimethoxybenzamide as thesole product in 97% yield.Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com