• 作者： 許博治 ; 黃倉淼 ; 蔡福裕 等
• 作者服務機構： 台灣大學化學系
• 中文摘要： Synthesis of square-planar trans dialkyl and alkyl aryl complexes of platinum(II), trans-Pt(R)(R')(PPh/sub 3/)/sub 2/ (R=MeR'=Et (2a); R=MeR'=Ph (2b); R=R'=Et (2c); R=EtR'=Ph (2d)) was established employing transmetalation of trans-Pt(R)(I)(PPh/sub 3 /)/sub 2/ with Grignard reagents R'MgX. Complexes (2a-2c) underwent stereoselective carbonylation to produce cis-Pt(R)(COR')(PPh/sub 3/)/sub 2/(R=MeR'=Et (3a); R=MeR'=Ph (3b); R=R'=Et (3c)). These facile transformations were exclusive and quantitative. The reactivity of carbonylation followed the order Et>Ph>Me. A similar reaction of (2d) with CO yielded EtC(O)Ph instead. The cis acyl alkyl or acyl aryl complexes (3a)-(3c) suffered substitution of CO for a PPh/sub 3/, leading to two isomers SP-4-3- and SP-4-4-Pt(PPh/sub 3/)(CO)(COR')(R)(R=MeR'=Et (4a, 4a'); R=MeR'=Ph (4b, 4b'); R=R'=Et (4c, 4c'), respectively. The reverse reactions of (4) to (3) readily occurred when external PPh/sub 3/ was provided. The stereoselectivity of carbonylation of trans-Pt(R)(R')(PPh/sub 3/)/sub 2/ is explained by a mechanism in which reversible displacement of a PPh/sub 3/ by CO in the reactant precedes to form a four-coordinate dialkyl carbonyl intermediate Pt(PPh/sub 3/)(CO)(R)(R'). The ensuing alkyl(or aryl) migration from metal to the carbonyl carbon achieves the cis acyl alkyl (or aryl) configuration. Recoordination of a PPh/sub 3/ completes the reaction. X-ray structures of (2b), (2c), (3b) and (4b) as single crystals are provided.
• 英文摘要： --
• 中文關鍵字： Insertion Reaction; Carbonylation; Stereoselectivity; Grignard Reagent; Platinum Complex; Single Crystal Structure
• 英文關鍵字： 插入反應；羰基化；立體選擇性；格任亞試劑；鉑錯合物；單晶結構