1 -hexene-sulfone

The high sensitivity of poly(olefin sulfone)s to chain scission by radiation was first discovered for poly(l-butene sulfone) and poly( 1-hexene sulfone) by Brown and O Donnell79,80. 

Figure 12.2.1. Result for a Py-GC/MS analysis of po y(1-hexene sulfone). Pyrolysis done on 0.4 mg material at 600° C In He, with the separation on a Carbowax type column.

Table 12.2.2. Compounds identified in the pyrogram of poly(1-hexene sulfone) as shown in Figure 12.2.1.

Results for a Py-GC/MS analysis of poly(l-hexene-sulfone) CAS 34903-07-6 with the idealized structure [-CH(C4H9)-CH2-S02-CH2-CH(C4H9)-S02- ] are shown in Figure 12.2.1. The pyroiysis was done in similar conditions as for other examples, at 600° C in... 

As seen from Table 12.2.2, the main pyrolysis products of poly(l-hexene-sulfone) are SO2 and 1-hexene. However, some other fragment molecules are generated by various types of reactions such as hydrogen transfer, cyclization, etc. Typical examples are 2-ethylthiophene, 3-ethylthiophene, and 2,5-dibutylthiophene. 

Poly(l-hexene sulfone) 148.23 Poly(3-chloropropylene oxide) 92.53... 

In the reaction of a-sulfonyl carbanion with lactones, the corresponding hydroxy-co-ketosulfones were obtained " . Thus, various o-hydroxyketones were shown by Umani-Ronchi and coworkers to be formed from the corresponding lactones. For example, the reaction of a, a-dilithioalkyl phenyl sulfones with lactones in THF at low temperatures afforded co-hydroxy-jS-ketosulfones which, upon desulfonylation with aluminium amalgam, gave the corresponding hydroxyketones . This process was applied for the syntheses of cis-jasmone and dihydrojasmone by treating y-valerolactone with ds-3-hexen-l-yl phenyl sulfone and n-hexyl phenyl sulfone. ... 

For the addition of ethylene, EtOAc as solvent was particularly advantageous and gave 418 in 60% yield (Scheme 6.86). The monosubstituted ethylenes 1-hexene, vinylcyclohexane, allyltrimethylsilane, allyl alcohol, ethyl vinyl ether, vinyl acetate and N-vinyl-2-pyrrolidone furnished [2 + 2]-cycloadducts of the type 419 in yields of 54—100%. Mixtures of [2 + 2]-cycloadducts of the types 419 and 420 were formed with vinylcyclopropane, styrene and derivatives substituted at the phenyl group, acrylonitrile, methyl acrylate and phenyl vinyl thioether (yields of 56-76%), in which the diastereomers 419 predominated up to a ratio of 2.5 1 except in the case of the styrenes, where this ratio was 1 1. The Hammett p value for the addition of the styrenes to 417 turned out to be -0.54, suggesting that there is little charge separation in the transition state [155]. In the case of 6, the p value was determined as +0.79 (see Section 6.3.1) and indicates a slight polarization in the opposite direction. This astounding variety of substrates for 417 is contrasted by only a few monosubstituted ethylenes whose addition products with 417 could not be observed or were formed in only small amounts phenyl vinyl ether, vinyl bromide, (perfluorobutyl)-ethylene, phenyl vinyl sulfoxide and sulfone, methyl vinyl ketone and the vinylpyri-dines. 

In 1975 Kuntz has described that the complexes formed from various rhodium-containing precursors and the sulfonated phosphines, TPPDS (2) or TPPTS (3) were active catalysts of hydroformylafion of propene and 1-hexene [15,33] in aqueous/organic biphasic systems with virtually complete retention of rhodium in the aqueous phase. The development of this fundamental discovery into a large scale industrial operation, known these days as the Ruhrchemie-Rhone Poulenc (RCH-RP) process for hydroformylation of propene, demanded intensive research efforts [21,28]. Tire final result of these is characterized by the data in Table 4.2 in comparison with cobalt- or rhodium-catalyzed processes taking place in homogeneous organic phases. 

Water-soluble l,3-bis(di(hydroxyalkyl)phosphino)propane derivatives were thoroughly studied as components of Pd-catalysts for CO/ethene (or other a-olefins) copolymerization and for the terpolymerization of CO and ethene with various a-olefins in aqueous solution (Scheme 7.17) [59], The ligands with long hydroxyalkyl chains consistently gave catalysts with higher activity than sulfonated DPPP and this was even more expressed in copolymerization of CO with a-olefins other than ethene (e.g. propene or 1-hexene). Addition of anionic surfactants, such as dodecyl sulfate (potassium salt) resulted in about doubling the productivity of the CO/ethene copolymerization in a water/methanol (30/2) solvent (1.7 kg vs. 0.9 kg copolymer (g Pd)" h" under conditions of [59]) probably due to the concentration of the cationic Pd-catalyst at the interphase region or around the micelles which solubilize the reactants and products. Unfortunately under such conditions stable emulsions are formed which prevent the re-use... 

In a quest for a more environment-friendly process it has been found that reaction 8.4 can be catalyzed by Pd(II) complexes of various nitrogen-donor ligands (Scheme 8.1) under not too harsh conditions (100 °C, air) without the need of copper chlorides [10,11]. Of the investigated ligands, sulfonated batophenanthroline proved to be the best. Higher olefins, such as 1-hexene or cyclooctene were similarly transformed by this catalyst. Very importantly, there was no isomerization to internal olefins and 2-hexanone was formed with higher than 99 % selectivity. This outstanding selectivity is probably due to the absence of acid and Cu-chlorides. 

A.A. Jones, Clark Univ., Mass. I would tend to agree with the dynamic picture you presoited. The idea that the high frequency motion in the sulfone hexene type polymers doesn t cause a net relaxation of dipoles but moves the magnetic dipole-dipole interaction around to cause nuclear relaxation is, I think, the crux of the matter. 

Replacement of tppts by the fluoro substituted sulfonated ligand 4 [Table 2 94% (n=l) and 6% (n=0)] in the rhodium-catalysed hydroformylation of 1-hexene in a two phase system increased the selectivity to linear aldehyde n-heptanal from 86% to 93% at the low P/Rh molar ratio of 7.5/1.75,76 The Rh/4 catalyst was quantitatively recovered after the reaction by simple decantation.75,76 The moderate increase of the n/i ratio is of interest when one considers that ligand 4 is mainly present as the disulfonated species (94%) compared to the trisulfonated compound tppts and that tris(4-fluorophenyl)phosphine is less basic (pKa=1.97) than triphenylphosphine (pKa=2.73).376 In rhodium-catalysed hydroformylation reactions in organic solvents it is known that electron withdrawing substituents, which increase the -acidity of the ligand, give rise to an increase in the n/i ratio.377 379... 

Rhodium catalysts generated from the sulfonated phosphine 23 (Table 2) were effective in the hydrogenation of olefins in an aqueous/organic or in a homogeneous methanol system, substantially higher rates being observed in the latter system.131 For example, the TOF observed in the hydrogenation of 1-hexene in the biphasic system was 220 h 1 compared to 7860 h 1 in methanol.131... 

A = 1-Hexene, B = Tetramethylene Sulfone, C= Benzene, Represented in Figure 14.1 466... 

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