Hydroformylation of Other Lower Olefins and Dienes

2 Hydroformylation of Other Lower Olefins and Dienes - Lower olefins such as 1-butene or 1,3-butadiene are hydroformylated with acceptable rates using Rh/tppts catalysts according to the RCH/RP process. Hoechst AG Werk Ruhrchemie has developed an attractive new process350 for the hydroformylation of raffinate II, a mixture of 1-butene, cis- and /r my-butene-2 and n- and i-butane derived from the C4 stream of naphtha crackers (after removal of 1,3-butadiene 

The advantages of this new process are the high n/i ratio and the low formation of heavy ends (1.5%) and alcohols (1%) without any formation of formates. In the original cobalt-based high-pressure process the n/i ratio was 67/33, with substantial formation of heavy ends (6.7%), alcohols (6.6%) and pentylformates (4.2%).350 The n-valeraldehyde product is oxidized with molecular oxygen to n-valeric acid, the trimethylolpropane, pentaerythritol, or dipentaerythritol esters of which are used as lubricants.350 

DSM370 has patented platinum systems based upon tetrasulfonated bidentate water soluble ligand 29 (Table 2 x=4, m=0, n=0) as catalysts for the hydroformylation of a mixture 1-butene (45%) and 2-butene (22%) with 33% butane at 100°C and 80 bar CO/H2 in an aqueous/methanol (300/32), CF3SO3H acidic medium. The olefin conversion was 86% and the selectivity to the aldehydes 95% (n/i ratio of 2.8) together with small amounts of aldolcondensation products and acids. The products were isolated from the aqueous catalyst mixture leaving the reaction zone by extraction with ether and the aqueous phase recycled to the reactor. 

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