Organotin compounds bearing mesogenic sidechains: synthesis, X-ray structures and polymerisation chemistry

Reduction of C,O-chelated organotin(IV) dichlorides and dihydrides leading to protected polystannanes

“…Vinyl ethers, 1e4, were synthesized following methods reported in literature [3,16,17]. Compounds 5e8 were synthesized via known radical hydrostannylation reactions utilizing azobisisobutyronitrile (AIBN) as a radical initiator [3].…”

“…Compounds 5e8 were synthesized via known radical hydrostannylation reactions utilizing azobisisobutyronitrile (AIBN) as a radical initiator [3]. When an equimolar amount of vinyl ether (1e4) and triphenyltin hydride were used, a significant amount (>20%) of hexaphenylditin ( 119 Sn NMR (C 6 D 6 ) d: À143 ppm) was always observed.…”

“…In this respect, polystannanes distinguish themselves from homopolymers of Si or Ge by having a backbone of covalently bonded metal (Sn) atoms. As a result, the diffuse orbitals of tin bonds in polystannanes display a greater degree of s-delocalization compared to polysilanes and polygermanes, leading to lower intrinsic energy gaps (>390 nm, 70 nm or more red-shifted vs. Si) and greater metallic character [3] These intriguing polymers are envisioned for uses as processable intrinsic semiconductors [4] or printable polymeric wires. Light and moisture sensitive high molecular weight polystannanes have been successfully synthesized by a number of routes including reductive coupling of organotin dihalides or the catalytic dehydrocoupling of organotin dihydrides, respectively [4].…”

“…1) were first isolated and structurally characterized by Molloy et al [3] The X-ray structure determination of 11 revealed the presence of a substantive dative interaction between oxygen and tin atoms (SneO ¼ 2.918(7) Å). However, attempts by these researchers to polymerize the tethered oxypropyl 11 through Na Wurtz coupling were unsuccessful whereas both the longer oxobutyl and oxohexyl derivatives readily polymerized under these conditions.…”

Hydrogermolysis reactions involving the α-germylated nitriles R3GeCH2CN (R=Ph, Pri, But) and germanium amides R3GeNMe2 (R=Pri, But) with Ph3GeH: Substituent-dependent reactivity and crystal structures of Pri3GeGePh3 and But3Ge[NHC(CH3)CHCN]

“…Well-developed methods for the preparation of silicon- [1][2][3][4][5][6][7][8][9][10][11] and tin- [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28] containing oligomers and polymers have been known for some time. In the case of germanium, until recently existing methods for the synthesis of oligomeric systems have been complicated by low yields and/or the formation of mixtures of products .…”