Potassium phosphate, tert

M potassium phosphate buffer, pH 7 aqueous glucose solution ketoreductase enzyme (Codexis Inc) glucose dehydrogenase enzyme (Codexis Inc) methyl tert-butyl ether (MTBE)... 

Naphthalene, Molten Antimony Potassium Tartrate Ammonium Tartrate Antimony Potassium Tartrate Antimony Potassium Tartrate Tert-Butylamine Tricresyl Phosphate Calcium Phosphate DDD... 

Heck and Suzuki type couplings have been described by Fu [2] et al. The reaction of chlorobenzene and styrene in refluxing dioxane in the presence of [Pd2(dba)3 ] and the electron rich tri-tert.-butyl-phosphane [eq. (a)] gives rise to trans-stilbene in 83% yield. Besides the choice of the ligand - aryl phosphanes, tri-n-butyl-phosphane or tri-cyclo-hexyl-phosphane show no conversion - the base is also crucial for success. Cesium carbonate gives the best results, although the cheaper potassium phosphate gives comparable yields. 

Discrete copper compounds can also be used as catalysts for the synthesis of arylamines (Scheme 3.52) [58]. Venkataraman used a neocuproine-ligated copper(I) species to promote the coupling of aryl halides with secondary amines. A practical advantage to this chemistry was that only air-stable materials were needed to construct the catalyst needed for the cross-coupling. A base was needed to promote the reaction, and potassium tert-butoxide was found to be more effective in the cross-coupling than other common bases including potassium phosphate, sodium methoxide, or cesium carbonate. Curiously, cesium carbonate was not as active in this chemistry, but it was quite effective in the preparation of diaryl ethers. Several aryl halides were screened for activity, and aryl bromides and iodides afforded moderate to good yields of the arylamines. It should be noted that an electron-neutral aryl chloride was converted into the triarylamine, albeit in lower yield (49%). 

Sodium enolates of diethyl 2-oxoalkylphosphonates react with diethyl chlorophosphate to produce enol phosphates. Low-temperature treatment of enol phosphates with tert-BuOK induces the ()-elimination of potassium diethyl phosphate and formation of diethyl 1-alkynylphosphonates in good yields (43-95%, Scheme 7.113). However, the reaction is prone to prototropic isomerization and diethyl 2-oxobutyIphosphonate leads to a mixture of diethyl 1-butynyIphosphonate (43%) and diethyl 2-butynylphosphonate (51%). ... 

TBAF is very useful for alkylation of nucleic acid derivatives. Methylation or benzylation of uracil gives almost quantitative yields of alkylated product when using alkyl bromides, diaUcyl sulfates (eq 17), trialkyl phosphates, or alkyl chlorides with TBAF. Alkylation of the thiol anions generated from deprotection by 1,2-dibromoethane produces interesting tetrachalcogenofulvalenes. Under phase-transfer conditions, selective mono- and dialkylations of malononitrile have been achieved by using neat TBAF with Potassium Carbonate or Potassium tert-Butoxide and controlling the amount of alkyl bromides or iodides used (eqs 18 and 19). ... 

Potassium ) (/ =3/2). Three G-quadruplex structures formed by self-assembly of 5 -tert-butyl-dimethylsilyl-2, 3 -0-isopropylidene guanosine, gua-nosine and GMP were studied by solid-state NMR, and NMR spectra clearly show different spectral signatures for K+ ions inside the G-quadruplex channel and for ions bound to the phosphate groups. ... 

Another illustration from the author s experience is the differences in percent recovery when hexane is used versus methyl tert-butyl ether (MTBE), to elute off of a CIS sorbent. Two different aqueous matrices were spiked with the OPs diazinon and malathion. In one series of experiments, two 500-/xL aliquots of hexane were used to elute off of the eartridge followed by two 500-/aL aliquots of MTBE eluted off the same eartridge. The same experiment was performed on a second aqueous matrix that was more acidic by virtue of adding potassium dihydrogen phosphate (KH2PO4). The results are shown in Table 3.14. It is clearly evident that... 

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