Phenyl [0]betylate fluorosulfate (2), the first example of a "[0]betylate" (trialkylammoniosulfate ester), has been prepared by methylation of phenyl N,N-dimethylsulfamate with methyl fluorosulfate. Nucleophiles react with 2 either by attack on the sulfur or methyl carbon atoms, but with no sign of any products derived from benzyne or the phenyl cation. A synthesis of enol N,N-dimethylsulfamates has been devised using a reagent, [Formula: see text], prepared from tetramethylsulfamide and methyl fluorosulfate, but no satisfactory method was found for converting the sulfamic ester to the [0]betylate. Evidence is presented that phenyl chlorosulfate reacts with trimethylamine to give the phenyl [0]betylate which then undergoes further reaction.

. Can. J. Chem. 59,362 (1981). Unhindered primary alkyl N,N-dimethylsulfamates (1) react with methyl fluorosulfate to give the corresponding alkyl fluorosulfates (3) and the betaine, M~,&so,-(4), evidently by way of the intermediate alkyl [Olbetylate fluorosulfate (2); with certain other alkyl esters (1) products of substitution, elimination, and rearrangement are formed. The reaction not only provides a potentially useful route to simple alkyl fluorosulfates, but serves to demonstrate the powerful nucleofugality of the [Olbetylate group. To obtain a method for predicting the reactivity of [Olbetylates, we have compared substituent parameters with rate constants in four series of nucleophilic displacements involving esters of the general structure ROS02Z; correlation (of log k) with o* is mediocre but a new parameter, o : , with a "15% resonance" contribution as defined by Swain and Lupton, gives good to excellent agreement in the four reaction series. Evidence is presented for formation of the 7-norbornyl cation via the [Olbetylate from 7-norbornyl N,N-dimethylsulfamate and methyl fluorosulfate. Comparison with what is known of the reactivities of 7-norbornyl p-toluenesulfonate and trifluoromethanesulfonate esters serves to confirm that [0] betylates are among the most nucleofugal functions of which a derivative has been fully characterized.JAMES FREDERICK KING et TERESA MEE-LING LEE. Can. J. Chem. 59,362 (1981). Introduction more reactive than even the "super sulfonates". In the accompanying paper (1) we have reported Accordingly when we had determined that an aryl that phenyl N,N-dimethylsulfamate reacts with [Olbet~late could be prepared from an aryl N,Nmethyl fluorosulfate to yield the first example of an dimethylsulfamate, we quickly turned our attention isolable "[Qlbetylate" (i.e. trialkylammoniosul-to the corres~onding reaction of alkyl N,Nfate) ester.2 dimethylsulfamates. This paper describes our study of this reaction and our observation of the