The Reactions of Aryl Tin(II) Hydrides {AriPr6Sn(μ-H)}2 (AriPr6 = C6H3-2,6-(C6H2-2,4,6-iPr3)2) and {AriPr4Sn(μ-H)}2 (AriPr4 = C6H3-2,6-(C6H3-2,6-iPr2)2) with Aryl Alkynes: Substituent Dependent Structural Isomers

The reactions of the aryl tin(II) hydrides {AriPr6Sn(μ-H)}2 (AriPr6 = C6H3-2,6-(C6H2-2,4,6-iPr3)2) and {AriPr4Sn(μ-H)}2 (AriPr4 = C6H3-2,6-(C6H3-2,6-iPr2)2) with aryl alkynes were investigated. Reaction of {AriPr6Sn(μ-H)}2 and {AriPr4Sn(μ-H)}2 with 2 equiv of diphenyl acetylene, PhCCPh, afforded the aryl alkenyl stannylenes AriPr6SnC(Ph)C(H)Ph (1) and AriPr4SnC(Ph)C(H)Ph (2). In contrast, the analogous reactions of {AriPr6Sn(μ-H)}2 with 2 equiv of phenyl acetylene, HCCPh, afforded a high yield of the cis-1,2 addition product AriPr6(H)SnC(H)C(Ph)Sn(H)AriPr6 (3), which has a four-membered Sn2C2 core structure comprised of two Sn–Sn bonded Sn(H)AriPr6 units bridged by a −C(H)═C(Ph)– moiety. The corresponding reaction of the less bulky hydride {AriPr4Sn(μ-H)}2 with 2 equiv of phenyl acetylene leads to AriPr4SnC(H)C(Ph)Sn(H)2AriPr4 (4) which unlike 3 has no Sn–Sn bonding. Instead, the tin atoms are connected solely by a −C(H)═C(Ph)– moiety. Each tin atom carries a AriPr4 substituent but one is also substituted...