The direct, facilq reaction between sulfur dioxide and the common silylating agent hexamethyldisilazane (HMDS) resulting in the formation of 1, 1, 1-trimethyl-N-sulfinylsilanamine, (CH 3 ) 3 Si—N=S=0 (1), has not previously been reported, although sulfur dioxide is known to react with bis-(trimethylsilyl)diimine1 and Me 3 SiHgSiMe 32 to form the unstable bis(trimethylsilyl) sulfoxylate (CH 3 )3 Si—O—S—O—Si(CH3)3 (2). Compound 1 was first made in 1966 from the reaction of tris(trimethylsilyl)amine with thionyl chloride at 70 °C in the presence of A1C1 3 catalyst. 3 Since that time a number of other synthetic methods have also been reported for its formation. 4-8 It should be noted that the germanium. © 1980, American Chemical Society. All rights reserved.