The aryl(silyl)aminotrichlorosilane 2,6-iPr2C6H 3N(SiMe2Ph)SiCl3 (1) and aryl(phosphanyl) aminotrichlorosilane ArN(PPh2)SiCl3 (Ar = 2,6-iPr 2C6H3 (2), 4-MeC6H4 (3), 2,4,6-Me3C6H2 (4)) were prepared and utilized for investigation in reactions with freshly prepared lithium alkynyls. Reaction of 1 with PhC≡CLi resulted in the compounds PhMe2SiC≡CPh and 2,6-iPr2C6H3N[Li(THF)3] Si(C≡CPh)3 (5), while 2 reacted with R′C≡CLi to produce the compounds Ph2PC≡CR′ and [2,6-iPr 2C6H3NSi(C≡CR′)2] 2 (R′ = Ph (6), tBu (7), CH2CH2Ph (8)). Reaction of 3 with PhC≡CLi led to the formation of Ph2PC≡ CPh and [4-MeC6H4NSi(C≡CPh)2]3 (9a) as a major product and 4-MeC6H4NSi(C≡CPh) [N(4-MeC6H4)Si(C≡CPh)3]2 (9b) as a minor product. When 4 was reacted with PhC≡CLi, [2,4,6-Me 3C6H2NSi(C≡CPh)2]2 (10a) was isolated as the major product while [(2,4,6-Me3C 6H2)3N3Si2(C≡CPh) 4Li(THF)]-[Li(THF)4]+ (10b) was the minor product. The formation of Ph2PC≡CPh was also detected. All reported compounds were characterized by multinuclear NMR (1H, 13C, 29Si, and/or 31P) and/or IR spectroscopy, and compounds 2, 5-8, 9a, and 10b were further distinguished by single-crystal X-ray crystallography. These results exhibit a route to the Si2N 2- or Si3N3-based cyclosilazanes 6-8, 9a, 9b, and 10a via the N-P bond cleavage of the aryl(phosphanyl)aminotrichlorosilanes during multiple metathesis reactions. © 2014 American Chemical Society.