Charge 1-octene

Since the solubility of long-chain alkenes is higher in ionic liquids than in water, there is much interest in finding effective ionic liquid catalysts for the hydroformylation reaction. Bis-phosphines have proved to be particularly useful in hydroformylation reactions and a bis-phosphine with a charged cobaltocenium backbone, analogous to l,l/-bis(diphenylphosphino)ferrocene (dppf), has been developed specifically for use in ionic liquid hydroformylation reactions [26], In combination with [Rh(CO)2(acac)], the 1, I -bis(diphenylphosphino)cobaltocenium hexafluorophosphate ligand dissolved in [bmim][PF6] effectively catalyses the hydroformylation of 1-octene as shown in Scheme 8.11. 

The scope of SILP was extended by investigating charged monophosphine ligands, as well as liquid-phase CF hydroformylation. The latter was demonstrated on 1-octene using the SILP Rh-(NORBOS-Cs3)/ [bmim][PF6]/silica catalyst. The authors recognize that the supported catalyst-phihc phase offers the significant advantage of very efficient ionic liquid use. 

A flask is charged with finely powdered molecular sieves (4 A, 50 mg), magnesium turnings (97 mg, 4.0 mmol), titanocene dichloride (249 mg, 1.0 mmol), THE (5 mL), triethyl phosphite (0.34 mL, 326 mg, 2.0 mmol) and 1-octene (224 mg, 2.0 mmol), in the order given. The resulting mixture is stirred for 2 h at room temperature and a solution of 2 [( )-2-phenylethenyl]-l,3-dithiane (111 mg, 0.5 mmol) in THF (2 mL) is added. The mixture is stirred for 4 h and then diluted with hexane (30 mL). Filtration through Celite, concentration of the filtrate, and purification of the product by preparative TLC gives 82 mg (72%) of the title compound as a mixture of cis and trans cyclopropanes (cis/trans 60 40). 

As mentioned earlier, in the Ruhrchemie-Rhone Poulenc process for propene hydroformylation the pH of the aqueous phase is kept between 5 and 6. This seems to be an optimum in order to avoid acid- and base-catalyzed side reactions of aldehydes and degradation of TPPTS. Nevertheless, it has been observed in this [93] and in many other cases [38,94-96,104,128,131] that the [RhH(CO)(P)3] (P = water-soluble phosphine) catalysts work more actively at higher pH. This is unusual for a reaction in which (seemingly) no charged species are involved. For example, in 1-octene hydroformylation with [ RhCl(COD) 2] + TPPTS catalyst in a biphasic medium the rates increased by two- to five-fold when the pH was changed from 7 to 10 [93,96]. In the same detailed kinetic studies [93,96] it was also established that the rate of 1-octene hydroformylation was a significantly different function of reaction parameters such as catalyst concentration, CO and hydrogen pressure at pH 7 than at pH 10. 

It could also be shown by Berkessel and coworkers that the ionic liquid l-n-octyl-3-methyUmidazolium bis(trifluoromethanesulfon)amide [omim] [BTA] can replace HFIP as solvent (Scheme 98) . In this reaction medium, 1-octene and vinylcyclohexane, which are generally unreactive substrates under most of the known procedures in the literature, were epoxidized by phenylarsonic acid (4%) in 6 to 6.5 hours in the presence of 50% hydrogen peroxide with yields of 68 and 80%, respectively. The [BTA] anion seems to be essential for good epoxidation results, since other ionic liquids with different anions this anion did not affect the desired conversion. For the epoxidation in HFIP a charge... 

A 1-1., three-necked, round-bottomed flask is fitted with a mechanical stirrer, a reflux condenser attached to a Dean-Stark water separator, and a 250-ml. dropping funnel. The flask is charged with 25.0 g. (0.16 mole) of 3,7-dimethyl-6-octenal (Note 1) and 500 ml. of toluene. The solution is heated to reflux with stirring, and a solution of iV-methylhydroxylamine, methanol, and toluene is added (see below). 

Charge the flame dried and argon flushed three-necked flask with 1-octene. Cool to 0°C, add triethylborane, and slowly the borane-methyl sulfide complex. 

A 50-mL pressure bottle equipped with a magnetic stirring bar was charged with 1-octene (l.Ommol) in THE (0.5 mL)). A 0.5M solution of 9-BBN in THE (1.1 mmol) was added... 

Oxidation of 1-octene to 2-octanone. The reactor was charged with Pd(OAc)2 (17 mg), hydroquinone (25 mg), FePc or CoSp (0.076 mmol), and distilled N,N-dimethylformamide (1 mL). To this 0.12 mL of water and 8 (iL of 60% aqueous HCIO4 were added. The reactor was purged with oxygen, and 1-octene (0.17 g, 1.5 mmol) was added. The reactor was stirred at room temperature and the oxygen uptake was measured. 

Circularly polarised 190 nm radiation has been used to study the direct photoracemisation of the enantiomers of trans cyclo-octene (Inoue et al.), and new evidence has been reported for the 90° twisted intermediate on the SI surface of stilbene (Gano et al.). Intramolecular charge-transfer excitation of 4-dimethyl-amino-4 -cyanostilbene and 4-azetidinyl-4 -cyanostilbene is considered to involve at most an intermediate with a lifetime of less than 1 ps (lUchev et al.), and a novel synthetic route to 5,6-dihydro-4H-l,2-oxazines (26) from y,5-unsaturated oximes has been described by Armesto et al. The photorearrangement of the ammonium salts of the dibenzobarrelene (27) to the semibullvalene isomers has... 

It seems that practical implementation of this type of selective catalysts will require a medium in which (very) polar products can be removed from the zeolite phase. Unfortunately, no attention has been paid in literature to such issues. On the contrary, some attention has been devoted to host modification after exchange of NaY with other alkali metal cations [37]. The cyclohexene epoxidation activity increases with decreasing size of the charge compensating cation pointing to the influence of steric effects or of electrostatic effects on the activity. In competitive experiments using cyclohexene and 1-octene as feed, the reactivity of the smaller substrate is suppressed, indicating that competitive sorption is involved as well [37],... 

A. 2-Bromo-1 -octen-3-ol.2 A one-necked, 250-mL, round-bottomed flask equipped with a magnetic stirring bar and a rubber septum is charged with 70 mL of... 

The upper phase was recharged to the cleaned and catalytically inactive autoclave. A solution of 30 mL of 1-octene in 35 mL of toluene was added under 5 atm CO/H2 (1 1) and heated to 100°. The pressure was increased to 10 atm CO/H2 (1 1) and maintained for 24 hours. A GC analysis of the reaction mixture showed only trace amounts of conversion of 1-octene. In contrast, when the lower phase was charged to the autoclave, the hydroformylation of 1-octene proceeded to give 85% nonanals with nji ratio of 2.9 and 8% octenes. 

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