Triethyloxonium hexafluorophosphate

The synthesis of a dipeptide dihydrothiazole by way of an imidate is shown in Scheme 13.[521 The Boc-protected amino acid 37 (in this case Val) was converted into the primary amide 38 by the mixed anhydride coupling with ammonia. The amide was then directly converted into the imidate 39 using triethyloxonium hexafluorophosphate which was subsequently condensed with H-Cys-OEt to provide the dihydrothiazole 40. 

A suspension of Boc-Val-NH2 (38 2.0 g, 9.26 mmol) in dry CH2C12 (23 mL) was cooled to 0°C, treated with triethyloxonium hexafluorophosphate (2.55 g, 10.19 mmol), and the resulting soln was stirred at rt for 18 h. The mixture was then washed with sat. NaHC03, dried (Na2S04), and concentrated in vacuo to give 39 as a colorless oil which was used without further purification for the next step yield 2.17g (96%). 

The organolithium compound (214) is obtained by treatment of the tetrathiafulvalene (5) with lithium diisopropylamide (LDA). This lithium compound (214) can further react with carbon dioxide, ethyl chloroformate, acetyl chloride, formaldehyde, dimethyl sulfate, and triethyloxonium hexafluorophosphate to produce the correspondingly substituted tetrathiafulvalenes (215) (79JOC1476). 

The low molecular weight, 500 3000, polyepichlorohydrin glycol (PECHG) was prepared using triethyloxonium hexafluorophosphate (TEOP) initiator in the presence of various amounts of molecular weight modifiers, mostly ethylene glycol (EG). 

An alternative set of N values was reported by Kevill and Lin (NKL values) (60). As with N0Ts, the iN/mY equation (5) is employed, but the model substrates required to define the parameters are positively charged. Solvolyses of triethyloxonium hexafluorophosphate and tert-butylsulfonium ion define NKL values ... 

Figure 3. Percentage of reaction diverted to nitrate ester as a function of the concentration of added nitrate salt in the ethanolysis of 0.0038 M triethyloxonium hexafluorophosphate or ethyl iodide.

Other combinations of trialkyloxonium and Lewis acid are added to this group of salts, including triethyloxonium hexachloroantimonate (Et30+SbCl6 ) and triethyloxonium hexafluorophosphate (Et30 PF6 ). ... 

Deamination Aryidiazonium hexafluorophosphates. Aryldiazonium tetrahaloborates. Di-fluoroamine. Dinitrogen tetroxide (White). Hydroxylamine-O-sulfonic aeid. Hypophos-phorous acid. 3-Nitro-N-nitrosocarbazole. Nitrosyl chloride. Tetramethylurea. Debenzylation of benzoylamines Triethyloxonium fluoroborate. 

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