Building block monitoring

VARIABLES IN BUILDING-BLOCK MONITORING WITH MS/MS SCANNING... 

The goal of reaction monitoring is to optimize reaction conditions such as solvent, reagent ratio, temperature, concentration, mixing method, catalyst and others to push a reaction to completion. These reaction steps include the loading of scaffold, the building block additions, and the final cleavage from the polymer. 

Fmoc-Rink-Nle-pMeBHA-resin (1 g, 0.55 mmol g ) was swollen for 1.5 h in NMP in a reaction vessel equipped with a sintered glass bottom, and placed on a shaker. The Fmoc group was removed with 20% piperidine in NMP (8mL, 2 x 15 min) and after washing with NMP (8mL, 5 x 2 min), the Fmoc removal was monitored by the ninhydrin Kaiser test. Coupling of building blocks such as iV -Fmoc-/Va>-carb-oxyalkyl(OAl)Xaa-OH or /V -Fmoc-/V" -aminoalkyl(Aloc)Xaa-OH, or N -alkylated amino acids such as... 

Hence, such systems should induce interesting consequences on the structures and on the properties of materials thus obtained. For example, in the case of fluoroacrylic monomers, it is well-known that the crystallisation of perfluori-nated chains insures improvement of surface properties. In addition, by introducing well-defined fluorotelomers in the backbone or in the side chains, building block silicones can be synthesised with monitored thermal properties especially at low temperatures. 

For the recording of (helium I) spectra of volatile molecules or for gas-phase reactions monitored by PE spectroscopic real-time analysis in a flow system, the parts of a variable building block apparatus are assembled and directly connected to the spectrometer, which generates the compound stream by its respective vacuum pump system (Figure la and b). Out of numerous possible combinations11, only a few applications shall be pointed out (cf. Figure 1). 

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