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Palladium(0) Complexes( Dissertation 全文 ) Activation and Reactions of Si-Si and Si-Ge σ-Bonds by Title Bis(t-alkyl isocyanide)palladium(0) Complexes( Dissertation_全文 ) Author(s) Oike, Hideaki Citation Kyoto University (京都大学) Issue Date 1996-03-23 URL http://dx.doi.org/10.11501/3110570 Right Type Thesis or Dissertation Textversion author Kyoto University t SiYiL " + ma ; - b L s1--- -t k Lu 1 T g " " J - t 1030 ' i t ;tb- ' ' u' Ei7. )k:5ft pa } H+ - - , L--T b L Jh h t. J" s ' t wu " - , ' -"r vt - . L- li v- ' tl - ' ' IL r .y''[l yl Yx L. i ) n .t ' - li i FN ya L7 4L- 7 .-; , rLt - :v tv L " t- J-d Si-Ge 6,.B 'Activation and ReactionsLQf"Si-S-r e 1 an onds d T -r LV. ' -t1 it` -- - -of t 'f" L t.S r xtg- J by LBis(t-a!k. yl -lsoc yanl de) pallad tum-- (O)rComplexes ' i "n r l itt f'' ltJL i/ i r' , - t' -L' ttt r l F- .z - s ";" -;- .x )t ' rT't{ t - "- J i -t l " -?r ' +t - T ' J - Ntth t It -f t ' ' rg? e: "e , J ;-tl .. jLt Y="L Xt L . 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X' xl/;: ;--"i-r. tt .hr ; L -t.r -- u-g' - - iti ". N t-- ' i - ih-lt .y P- L) '.r nS .m;...,tl'Ltf.;' ,,Lii li.-.:` L}l.-f' tAL k. t!i '.X Jk .. T- +.'N S- 'C-fiL F -t i ) ..JÅq,ny;JII;.f` ."-;tMf""=S'[' - L '" '. 'S.- Fl' . rb eaki 1Oik'er f LI '- ` LL i v-Lj .S ` rr'".i•i- , Ce- Hid t ' :lr .t -; - -- r rvk t-f LtJ "t- 7f rt rr J t- td " - ry hf t .IPt t ""t-' ti: N- -b- .-.1`- i;"l,L?9I-(iilf"1,1',fL ','i, )1:L;"r" /1-'" i' ' , s'f=' m"' - L t? - IS fil- T.. 1-' '- ' L""'li .: . •-l:L ys ';"i ).: .z .t evic " v [ x' 'f s-L .-.ik ,kl 1/r"si ."' i' l..r).". 'il.s:e ;;i-.-Zt`i-'1 ', :r"El;.. IIf.vit-r ". f S; tf ' . T )1" cF tillÅq}..1:i'L.""'l,.. N"1thU'l' " .v . ktE 1 L)- .. " --' h."IJ'.,'r.].':.:+l{nl" :.;t., .--- l`;.fi "t, .'-.2.IIet2L l, .;f.. - .. 1. .]...;' eti "" .'t vt-'rN :,L11 'r/f , ' , " . i; S t- -".-NK .- J" vAJ.ft r- Nn .,g r` lls'tsD `X L-tlt,,- .:)-.'. -'.c.. s tL jN' t.i -- tE., - 'lr)-li. Fv k, gi-:,,:'i t -Jltlii';/lpl L) 1,r" ."I" -fit;.,-;;[)vli""Z tl Lr" -'it • - tH , 4 ;-i . t!- gN .t-..s - .v:1= , "fi lx.x .lt.".. t. , .- FlTT. Activation and Reactions of Si-Si and Si-Ge 6-Bonds by Bis(t-alkyl isocyanide)palladium(O) Complexes Hideaki Oike 1996 Preface The studies presented in this thesis have been carried out under the direction of Professor Yoshihiko Ito at Kyoto University during 1993-1996. The studies are con- cerned with activation and reactions of Si-Si and Si-Ge 6-bonds by bis(t-alkyl isocyanide)palladium complexes. The author wishes to express his sincerest gratitilde to Professor Yoshihiko Ito for his constant guidance, valuable suggestions, and hearty encouragement through out this work. The author is deeply grateful to Dr, Michinori Suginome for his con- tinuous advice and helpful discussions during course of this work. The author is also indebted to Associate Professor Masahiro Murakami, Dr. Masaya Sawamura, and Professor Kohei Tamao for their helpful suggestions, The author is fortunate to have had the great assistance ofMessrs. Mitsuru Sugawara, Sang-Soo Park, Miss Philippa H. Shuff, and Mr. Nobuhiko Takeda. The author is deeply grateful to Professor Tatsuya Shono who led the author to chemistry during 1991-1993. The author is thankful to Dr. Naoki Kise and other rnembers ofProf. Shono's group for their kind considerations. The author wishes to express his gratitude to Professor Yoshild Chujo for the measurement of molecular weight of polymers. The author wishes to thank to Mr. Tadao Kobatake and Mr. Haruo Fujita for the measurement of Mass and NMR spec- tra, respectively. The author is thankful to the staff at the Microanalysis Center of Kyoto University for the elemental analysis. The author wishes to thank to Dr. Eiji Ihara, Dr. Hitoshi Hamashima, and Dr. Minoru Hayashi for their kind advice. The author is thankilul to Messrs. Hideki Amii, Hajime Ito, Ryoichi Kuwano, Hiroshi Nakamura, Takafurni Ohara, and Akira Matsumoto for their kindness and good will in carrying out this work. Furthermore, he is sincerely grateful to Miss Chiyo Nagae and other members of Prof. Ito's re•- search group for their kind encouragement. The author thanks the Shin-Etsu Co. Ltd. and ASAI Germanium Research In- stitute for the donation of various chlorosilanes and germanium tetrachloride, respec- tively. iii Finally, the author express his deep appreciation to his family, especially his father, Mr. Yusai Dike and his late mother, Mrs. Mihoko Dike for their constant assistance and encouragement. Hideaki Dike Department of Synthetic Chemistry and Biological Chemistry Faculty ofEngineering Kyoto University 1996 IV Contents General Introduction -._-. -- --- -_. 1 Chapter 1 Stereoselective Synthesis of 1,2,4-Triols via Intramolecular Bis-Silylation of Carbon-Carbon Triple Bonds Followed by Hydrogenation <0 •••••••••••••••••••••••••••••••••••••••••• _ ••• -_.-.................... 7 Chapter 2 Reactions of Si-Si (I-Bonds with Bis(t-alkyl isocyanide)­ palladium(O) Complexes. Synthesis and Reactions of Cyclic Bis(organosilyl)palladium Complexes _...-................. 27 Chapter 3 Double Oxidative Addition of the Si-Si and Si-Ge (I-Bonds onto Isonitrile-Platinum(O) Complexes Leading to the Formation of Tetrakis(organosilyl)- and Bis(organogermy1)bis (organosilyl)platinum(IV) Complexes 71 Chapter 4 Synthesis of Organosilicon Macrocycles. Palladium-Catalyzed Ring-Enlargement Oligomerization of Cyclic Disilanes via Si-Si (I-Bond Metathesis······················· 95 List ofPublications ., -.-.............. 144 v General Introduction Today, in the field of organic chemistry as well as material science, group 14 organometallic compounds, especially organosilanes play an important role. For synthetic chemists, various selective transformations of organosilicon reagents have been useful and attractive in the construction of complex molecules.1 On the other hand, organosilicon polymers containing silicon-silicon bonds in which sigma elec­ trons delocalize have been of great interest in material science because of their unique chemical and physical properties.2 Furthermore, the chemistry of silicon has been extendeq. to germanium chemistry due to its close proximity to silicon in the periodic table. Therefore, the development of new methods for the selective fonna­ tion of silicon---earbon and silicon-silicon bonds has become more and more desir­ able. From this point of view, transition metal catalyzed reactions provide a new pathway to many organosilicon and related organogennanium compounds. In the coordination sphere of transition metals, the formation and cleavage of silicon-ele­ ment bonds occur under mild conditions. Over the past two decades, considerable attention has been focused on the pal­ ladium-catalyzed addition of Si-Si bonds to unsaturated compounds, Le., bis­ silylation, which forms two silicon--carbon bonds simultaneously.3 The reaction is considered to proceed through the mechanism shown in Scheme 1 for acetylene. The steps included are: (1) oxidative addition of the Si-Si bond to palladium(O), fonning bis(organosilyl)palladium(II), (2) formation of a 1t-complex with acetylene, (3) in­ sertion of the acetylene into one of the palladium-silicon bonds, and (4) reductive elimination of the bis-silylated product. In early investigations, reactive disilanes bearing electron-withdrawing groups or strained cyclic disilanes were required to obtain bis-silylated products in high yields. Since the calculated heat of reaction for the formation of bis(organosilyl)alkenes from substituted disilanes and acetylenes is ca. -40 kcal/ mol,4 even peralkylated (non-activated) disilanes should give products if a kineti­ cally favored reaction pathway is developed. In spite of many efforts, however, it was difficult to activate Si-Si bonds ofsuch disilanes using conventional palladium­ phosphine catalysts. Moreover, bis-silylation of alkenes was hardly achieved. 1 Scheme 1. (' 51-51 51 51, /51 Pd Ln During the last five years, much progress has been made in many aspects ofthis field.
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