Palladium-Catalyzed Insertion of Alkynes into the Sn-B Bond of a 2-Stannyl-2,3-dihydro-1H-1,3,2-diazaborole and X-ray Structure Analyses of 1,3-Di-tert-butyl-2[(Z)-2-phenyl-2-trim

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• 作者：Lothar Weber ; Henning B. Wartig ; Hans-Georg Stammler ; Anja Stammler ; and Beate Neumann
• 刊名：Organometallics
• 出版年：2000
• 出版时间：July 24, 2000
• 年：2000
• 卷：19
• 期：15
• 页码：2891 - 2895
• 全文大小：215K
• 年卷期：v.19,no.15(July 24, 2000)
• ISSN：1520-6041

文摘

Reaction of equimolar amounts of 1,3-di-tert-butyl-2-trimethylstannyl-2,3-dihydro-1H-1,3,2-diazaborole (1) with a series of alkynes R¹-CC-R² (2) (a: R¹ = H, R² = Ph; b: H, 4-ClC₆H₄;c: H, 4-BrC₆H₄; d: Ph, Ph; e: Me, Ph; f: Et, Ph; g: H, n-C₄H₉; h: Et, Et; i: H, n-C₆H₁₃) inthe presence of a catalytic amount of [Pd(PPh₃)₄] (2 mol %) regioselectively afforded highyields of the alkenes (Z)-R¹[B]C=C(R²)SnMe₃ (3a-h) ([B] = tBuNCH=CHN(tBu)B] as theresult of a cis-addition of the BSn bond of 1 to the acetylenic triple bond of 2. Spectroscopicevidence and X-ray structural analyses of 3a and 3f revealed that the bulky borolyl unitwas added to the least sterically hindered end of the CC multiple bond.