5-Stannaspiro[4.4]nona-1,3-diene, 6,6,9,9-tetrakis(trimethylsilyl)- | 173849-36-0

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 金属杂环化合物
• 英文名称: 5-Stannaspiro[4.4]nona-1,3-diene, 6,6,9,9-tetrakis(trimethylsilyl)-
• 英文别名: trimethyl-[1,4,4-tris(trimethylsilyl)-5-stannaspiro[4.4]nona-6,8-dien-1-yl]silane
• CAS: 173849-36-0
• 化学式: C₂₀H₄₄Si₄Sn
• 分子量: 515.621
• InChiKey: HSCWEOMGPFKDRS-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  7.42
• 重原子数：
  25
• 可旋转键数：
  4
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.8
• 拓扑面积：
  0
• 氢给体数：
  0
• 氢受体数：
  0

反应信息

• 作为产物：
  描述：

  bis[bis(trimethylsilyl)methyl]tin(II) 在 Acetylene;palladium;tri(propan-2-yl)phosphane 乙炔 作用下， 以 四氢呋喃 为溶剂， 以87%的产率得到5-Stannaspiro[4.4]nona-1,3-diene, 6,6,9,9-tetrakis(trimethylsilyl)-
  参考文献：
  名称：

  A Palladium-Catalyzed Stannole Synthesis

  摘要：

  A palladium-catalyzed (2 + 2 + 1) cycloaddition reaction of two C2H2 and one SnR(2) to form C-unsubstituted stannoles (C4H4)SnR(2) [R = CH(SiMe(3))(2) 2a, R(2) = {C(SiMe(3))(2)CH2}(2) 2c] is described. Catalysts are (R'(2)PC(2)H(4)PR'(2))Pd complexes (slow reaction) and (R'P-3)(2)Pd complexes (fast reaction). The mechanism of the catalysis has been elucidated in detail from stoichiometric reactions based on R = CH(SiMe(3))(2). For the [(R'(2)PC(2)H(4)PR'(2))Pd]-catalyzed system, the starting Pd(0)-ethene complexes (R'(2)PC(2)H(4)PR'(2))Pd(C2H4) (R' = Pr-i (3),(t)Bu (4)) react both with ethyne to give the Pd(0)-ethyne derivatives (R'(2)PC(2)H(4)PR'(2))Pd(C2H2) (R' = Pr-i (5), (t)Bu (6)) and with SnR(2) to yield the Pd(0)-Sn(II) adducts (R'(2)PC(2)H(4)PR'(2))Pd=SnR(2) (R' = Pr-i (7), (t)Bu (8)). The Pd-Sn bond [2.481(2) Angstrom] of 7 is very short, indicative of partial multiple bonding. Subsequent reactions of the Pd(0)-ethyne complexes 5 and 6 with SnR(2) or of the Pd(0)-Sn(II) complexes 7 and 8 with ethyne afford the 1,2-palladastannete complexes (R'2PC2H4-PR'(2))Pd(CH=CH)SnR(2) (Pd-Sn) (R' = Pr-i (10), (t)Bu (11)). The derivative with R' = Me (9) has also been synthesized. In 10 a Pd-Sn single bond [2.670(1) Angstrom] is present. Complexes 10 and 11 (as well as 7 and 8 but not 9) react slowly with additional ethyne at 20 degrees C to reform the Pd(0)-ethyne complexes 5 and 6 with concomitant generation of the stannole (C4H4)SnR(2) (2a). Likely intermediates of this reaction are the Pd(0)-eta(2)-stannole complexes (R'(2)PC(2)H(4)PR'(2))Pd(eta(2)-C(4)H(4)SnR(2)) (R' = Pr-i (12), (t)Bu (13)), which have been synthesized independently. The stannole ligand in 12, 13 is easily displaced by ethyne to yield 5 or 6 or by SnR(2) to yield 7 or 8. Thus, the isolated complexes 5-8 and 10-13 are conceivable intermediates of the catalytic stannole formation, and from their stoichiometric reactions the catalysis cycle can be assembled. For the [(R'P-3)(2)Pd]-catayyze system, the corresponding intermediates (Me(3)P)(2)Pd(C2H2) (15), ((Pr3P)-Pr-i)(2)Pd(C2H2) (17), (Me(3)P)(2)Pd=SnR(2) (18), ((Pr3P)-Pr-i)(2)Pd=SnR(2) (20), and (Me(3)P)(2)Pd(CH=CH)SnR(2) (Pd-Sn) (19) have been isolated or detected by NMR, and ((Pr3P)-Pr-i)(2)Pd(CH=CH)SnR(2) (Pd-Sn) (21) is postulated as an intermediate. The [(Me(3)P)(2)Pd] system (stannole formation above 0 degrees C) is catalytically more active than any of the [(R'(2)PC(2)H(4)PR'(2))Pd] systems (slow stannole formation for R' = (t)Bu at 20 degrees C). Most active is the [((Pr3P)-Pr-i)(2)Pd] system, allowing a catalytic synthesis of the stannole 2a from SnR(2) and ethyne at -30 degrees C [1% of 17; yield 2a: 87%; TON (turnover number): 87].By carrying out the catalysis in pentane at 20 degrees C (0.04% of 17), the TON is increased to 1074 but the yield of 2a is diminished to 43% due to uncatalyzed thermal side reactions.

  DOI：

  10.1021/ja952495b

文献信息

• A Palladium-Catalyzed Stannole Synthesis
  作者：Jochen Krause、Karl-Josef Haack、Klaus-Richard Pörschke、Barbara Gabor、Richard Goddard、Christian Pluta、Klaus Seevogel

  DOI：10.1021/ja952495b

  日期：1996.1.1

  A palladium-catalyzed (2 + 2 + 1) cycloaddition reaction of two C2H2 and one SnR(2) to form C-unsubstituted stannoles (C4H4)SnR(2) [R = CH(SiMe(3))(2) 2a, R(2) = C(SiMe(3))(2)CH2}(2) 2c] is described. Catalysts are (R'(2)PC(2)H(4)PR'(2))Pd complexes (slow reaction) and (R'P-3)(2)Pd complexes (fast reaction). The mechanism of the catalysis has been elucidated in detail from stoichiometric reactions based on R = CH(SiMe(3))(2). For the [(R'(2)PC(2)H(4)PR'(2))Pd]-catalyzed system, the starting Pd(0)-ethene complexes (R'(2)PC(2)H(4)PR'(2))Pd(C2H4) (R' = Pr-i (3),(t)Bu (4)) react both with ethyne to give the Pd(0)-ethyne derivatives (R'(2)PC(2)H(4)PR'(2))Pd(C2H2) (R' = Pr-i (5), (t)Bu (6)) and with SnR(2) to yield the Pd(0)-Sn(II) adducts (R'(2)PC(2)H(4)PR'(2))Pd=SnR(2) (R' = Pr-i (7), (t)Bu (8)). The Pd-Sn bond [2.481(2) Angstrom] of 7 is very short, indicative of partial multiple bonding. Subsequent reactions of the Pd(0)-ethyne complexes 5 and 6 with SnR(2) or of the Pd(0)-Sn(II) complexes 7 and 8 with ethyne afford the 1,2-palladastannete complexes (R'2PC2H4-PR'(2))Pd(CH=CH)SnR(2) (Pd-Sn) (R' = Pr-i (10), (t)Bu (11)). The derivative with R' = Me (9) has also been synthesized. In 10 a Pd-Sn single bond [2.670(1) Angstrom] is present. Complexes 10 and 11 (as well as 7 and 8 but not 9) react slowly with additional ethyne at 20 degrees C to reform the Pd(0)-ethyne complexes 5 and 6 with concomitant generation of the stannole (C4H4)SnR(2) (2a). Likely intermediates of this reaction are the Pd(0)-eta(2)-stannole complexes (R'(2)PC(2)H(4)PR'(2))Pd(eta(2)-C(4)H(4)SnR(2)) (R' = Pr-i (12), (t)Bu (13)), which have been synthesized independently. The stannole ligand in 12, 13 is easily displaced by ethyne to yield 5 or 6 or by SnR(2) to yield 7 or 8. Thus, the isolated complexes 5-8 and 10-13 are conceivable intermediates of the catalytic stannole formation, and from their stoichiometric reactions the catalysis cycle can be assembled. For the [(R'P-3)(2)Pd]-catayyze system, the corresponding intermediates (Me(3)P)(2)Pd(C2H2) (15), ((Pr3P)-Pr-i)(2)Pd(C2H2) (17), (Me(3)P)(2)Pd=SnR(2) (18), ((Pr3P)-Pr-i)(2)Pd=SnR(2) (20), and (Me(3)P)(2)Pd(CH=CH)SnR(2) (Pd-Sn) (19) have been isolated or detected by NMR, and ((Pr3P)-Pr-i)(2)Pd(CH=CH)SnR(2) (Pd-Sn) (21) is postulated as an intermediate. The [(Me(3)P)(2)Pd] system (stannole formation above 0 degrees C) is catalytically more active than any of the [(R'(2)PC(2)H(4)PR'(2))Pd] systems (slow stannole formation for R' = (t)Bu at 20 degrees C). Most active is the [((Pr3P)-Pr-i)(2)Pd] system, allowing a catalytic synthesis of the stannole 2a from SnR(2) and ethyne at -30 degrees C [1% of 17; yield 2a: 87%; TON (turnover number): 87].By carrying out the catalysis in pentane at 20 degrees C (0.04% of 17), the TON is increased to 1074 but the yield of 2a is diminished to 43% due to uncatalyzed thermal side reactions.