Part No: Issued year: 2007File size: 0.09mbFile type: pdf
PS-TBD (Figure 1) is a polystyrene bound guanidine base, which is stronger than corresponding resin bound DIEA (DIPEA) and bound N-Methyl-morpholine resins. It has a wide variety of uses in synthesis, from direct alkylation through to sequestering of acidic components of reaction.
Part No: P005Issued year: File size: 1.34mbFile type: pdf
An oxidation method using a novel solid phase oxidant, based on a covalently polystyrene bound, sulfonic ester linked 2,2,6,6-tetramethylpiperidine-1-oxyl species is presented, PS-TEMPO (Fig.1a&1b).1,2 The reagent showed fast room temperature kinetics compared to similar known systems3 when used to oxidize primary and secondary alcohols to aldehydes and ketones, respectively (Table 1). The products were in general of high purity and the isolated yields were good to excellent. The used reagent could be reactivated and reused for multiple oxidation reactions. The colour change observed as the oxidation state of the reagent changed, gave an indication of the extent to which the reagent had been used.
Part No: TN521Issued year: 2003File size: 0.05mbFile type: pdf
PS-Thiophenol is based on an aminomethyl resin with a tethered thiophenol functionality. The resin was
designed for the scavenging of alkylating agents, e.g. alkyl halides. PS-Thiophenol was tested and found
effective in scavenging alkylating agents ranging from octyl bromide to benzyl bromide. The scavenging
effectiveness of PS-Thiophenol was found to be greater than a polymer-bound benzyl thiol towards octyl
bromide, indicative of the higher nucleophilicity of the thiophenolate.
Part No: TN513Issued year: 2003File size: 0.03mbFile type: pdf
PS-Trisamine is an amine functional resin for the removal of excess electrophilic reagents during the quenching and purification of reaction mixtures.1 PS-Trisamine resin has a scavenging capacity of 3.0–4.0 mmol/g based on reaction with an excess of benzoyl chloride. Scavenging of common electrophiles typically requires 3–6 equiv of PS-Trisamine and occurs within 0.5–3 h at room temperature. The scope of PS-Trisamine as a scavenger for electrophilic reagents was investigated using 4-chlorobenzoyl chloride, 2-phenylbutyryl chloride and 2,6-dimethoxybenzoyl chloride as a series of acid chlorides with decreasing
reactivity.Acid chlorides were completely scavenged in 0.5 h using 3.5 equiv PS-Trisamine (Table 1). The presence of a tertiary base, e.g. PS-DIEA or PS-NMM, reduces the amount of PS-Trisamine required in the reaction by removing the hydrogen chloride formed. In addition to acid chlorides, benzenesulfonyl chloride and 4-methoxyphenyl isocyanate were effectively scavenged in 0.5 h.
Part No: TN123.06Issued year: 2006File size: 0.07mbFile type: pdf
This Chemistry Data Sheet details the use of ISOLUTE PE-AX, a strong anion exchange sorbent, for the
purification of acidic products from organic synthesis mixtures containing non-acidic reagents or by-products.
Part No: Issued year: 2013File size: 0.67mbFile type: pdf
We have successfully developed a rapid and efficient microwave-assisted protocol for the preparation of Neu5Ac congeners that are important intermediates for clinically-relevant derivatives of Neu5Ac. The syntheses were performed using readily available reagents, improved on established techniques, and used more benign reagent for peracetylation. Moreover, the protocol that we developed is 1 to 2 orders of magnitude faster than conventional methods.
Initiator+ SPWave synthesis system
Dhananjaya Sahoo, I. Abrrey Monreal, and Jonel P. Saludes
Part No: Issued year: File size: 0.18mbFile type: pdf
For high efficiencyin parallel synthesisand method developement short reaction timesare essential. We have examinedthe possibilityof maintaining reported selectivitiesin rapid, high temperaturepalladium-catalyzed asymmetric allylic alkylations. Reactions were promotedby useof singlemode microwave heating(vide infra),which oppositeto conventional oilbath heating(wallheat transfer) rapidlyand almost homogeneouslyheat largeparts of the sample(internalheat transfer).