Trimethyloxonium fluoborate

Teiuethyl-2,4-cyceohexadie-none, 46,115 dimenzation of, 46,117 Trimethyloxonium fluoborate, 46, 120... 

Trimethyloxonium fluoborate is only slightly soluble in dichloromethane. However, the use of a two-phase mixture presents no difficulties in either experimental procedure or yield. 

TRIMETHYLOXONIUM FLUOBORATE (Oxonium compounds, trimethyloxonium tetrafluoroborate)... 

Freshly prepared triethyloxonium fluoborate2 (170 g., 0 90 mole) is dissolved in 500 ml of anhydrous methylene chloride in a 1-1. three-necked flask equipped with a stirrer, gas-inlet tube, and drying tube (Note 1). The reaction flask is immersed in an ice bath, the stirrer is started, and 138 g. (3.00 moles) of dry dimethyl ether is passed into the solution from a tared cylinder over a period of about 2 hours The reaction mixture is allowed to stand overnight at room temperature An hour after the addition of dimethyl ether is complete, trimethyloxonium fluoborate begins to separate The initially liquid product solidifies slowly... 

Trimethyloxonium fluoborate is less hygroscopic and keeps better than triethyloxonium fluoborate, but it should be stored at 0-5° in a tightly closed screw-cap bottle.2 So stored, it can be kept at least a few weeks. 

This facile preparation is suitable for preparation of larger amounts of salt Like triethyloxonium fluoborate,2 trimethyloxonium fluoborate is a potent alkylating agent. In comparison with trimethyloxonium 2,4,6-trinitrobenzenesulfonate,5trimethyl-oxonium fluoborate is easier to make but does not keep quite as well on storage. 

This method for the preparation of trimethyloxonium 2,4,6-trinitrobenzenesulfonate is an adaptation of that described by the submitters.7 The salt can also be prepared from trimethyloxonium fluoborate by anion exchange.7 Trimethyloxonium fluoborate and hexachloroantimonate9-11 have been prepared by other methods. 

Methylation (of 497, R = Ph) by trimethyloxonium fluoborate produces the 2-quatemary salt (498), which isomerizes on basification, probably by a transient S—N bond cleavage, to 3-methylamino-5-phenyl-l,2,4-thiadiazole (499,95%).182... 

Triethyloxonium fluobotate [Oxonium, triethyl-, tetrafluoroborate(l-)), 59 TVTrifluoroacetylation, 122 Trimethyloxonium fluoborate [Oxonium, trimethyl-, tetrafluoroborate(l-),... 

Trimethyloxonium fluoborate 2,4,4-Trimethyl-2-pentanamine 2,2,3-Trimethylpentane 2,2,4-Trimethylpentane 2,3,3-Trimethylpentane... 

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