TPPMS biphasic conditions

Telomerizations have been among the first reactions tested under biphasic conditions [45, 190], starting with butadiene and methanol on Pd/TPPMS catalysts and yielding l-methoxy-2,7-octadiene. The telomerization in the presence of water as reactant (hydrodimerization cf Scheme 1) has been commercialized [15, 31, 42-44]. These biphasic developments of the Kuraray Corporation yield 1-octanol or 1,9-nonanediol, respectively (cf [15, 31, 42 4, 86, 133, 137, 244 e] and Section 2.3.5). Similar developments (but without technical realization) have been described by BASF [134], Mitsubishi [135], and Shell [136], and others [215 d, 242, 268]. The telomerization of butadiene and ammonia may also be biphasic [243]. 

Rh(I) complexes such as RhCl(TPPMS)3 4HzO, Rh(cod)Cl(TPPMS) H20, [Rh(cod)(/<2-Ph2P—C6H4-3-S02—0)]2 catalyze oligomerization of alkynes (propynoic acid, arylacetylenes) this has been studied only very recently in terms of biphasic catalysis. The Rh(I) complex Rh(cod)(/<2-Ph2P—C6H4-3-S02—0)]2 already reported by Wilkinson etal. [50] promotes the conversion of phenylacetylene to 1,2,4- and 1,3,5-triphenylbenzene under biphasic conditions (toluene/water) [58],... 

Diphenylacetylene and 1-phenyl-1-propyne were hydrogenated to the corresponding 1,2-disubstituted alkenes in aqueous-organic biphasic media at 50°C and 0.1 MPa H2, using the water-soluble catalyst [RuCl2(TPPMS)2]2 and an excess of TPPMS. The stereoselectivity of the reaction strongly depended on the pH of the catalyst-containing aqueous phase under acidic conditions, Z-alkenes could be obtained with selectivity close to 100% (81). The role of water was clari-fled by theoretical studies (82). 

Telomerization of 1,4-butadiene with water, alcohols, amines, and acids is an extremely useful reaction since it leads to the formation of practically important products. (179,180). For example, the telomer with water, 2,7-octadiene-l-ol can be further hydrogenated to 1-octanol which is a raw material for plasticizers for poly(vinyl chloride). In fact, this reaction was among the processes disclosed in the first patents on the use of TPPTS in biphasic solvent mixtures (58). The catalyst for such telomerizations usually consists of palladium(O) and an excess of TPPTS, TPPMS, or other water-soluble phosphines (eg, with quaternary ammonium substituents). The telomerization of 1,4-butadiene with water was developed into an industrial process by Kuraray Ind. (Scheme 26). Interestingly, the best ligand was the phosphonium salt shown in (Scheme 26) and the catalyst could be prepared in situ from this ligand and [Pd(OAc)2] (179). It is assumed that under the reaction conditions the corresponding tertiary phosphine can be formed to some extent and coordinates to palladium. In any case with a large excess of... 

Barbier-type carbonyl-allylations with allyl chlorides, acetates, or alcohols and SnCl2 can be catalyzed by the [PdCl2(TPPMS)2] catalyst in water-heptane biphasic systems (Scheme 37). The reactions proceed under very mild conditions (30-60°C) in most cases with jdelds higher than 95%, and the catalyst can be easily separated from the product (211). 

Unlike bromobenzene, benzyl chloride can be carbonylated in a biphasic system of heptane-water (Scheme 74) under very mild conditions. Both hydrophobic triphenyl-phosphine and amphiphilic TPPMS can serve as ligands for the process, which may mean that the reaction in this case may actually run at the interface. A strong acceleration of the reaction by anionic surfactants -C7Hi5S03Na or n-C7Hi5COONa is evidence in favor of this hypothesis.f ... 

It was found that RuHCl(TPPMS)2(THQ)2 and RuHCl(TPPMS)2(An)2 can be used as catalyst in a liquid-biphase hydrogenation of BT. The initial catalyst conditions were T = 136°C, P (H2) = 35 atm, 1 1 mixture of water/decalin. Under these experimental conditions, the only product detected was DHBT with no evidence of C-S bond cleavage [150]. 

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