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Isomerization-linear-hydroformylation is demanding, however, not an addressed issue, for production of value-added linear aldehydes by converting cheap and abundant internal alkenes available from bio- & petrochemical industry. In this paper, a dual metal catalysis system combining a Ru-isomerization catalyst and a Rh-linear-hydroformylation catalyst satisfying the “4S” criterions was reported for isomerization-linear-hydroformylation of C4 raffinate (mixed butenes) and internal olefins. The optimized dual metal catalyst system hydroformylated Raffinate II feed to valuable valeraldehyde in 98% linear selectivity (n:i = 49), 80% conversion and high activity of 1069 h⁻¹ TOF whereas 96% linear selectivity (n:i = 24), 71% conversion and 948 h⁻¹ TOF were observed using only the Rh-hydroformylation catalyst. Notably, valeraldehyde are produced in million tons scale annually for making non-toxic plasticizer DPHP. Various 2-olefins were also converted to linear aldehydes in > 98% linear selectivity (n:i > 49), 78%–82% conversion and high activity of 802–851 h⁻¹ TOF.

We herein report an efficient method to synthesize cyclic hydroxy ketones with a chiral quaternary center., We herein report an efficient method to synthesize cyclic hydroxy ketones with a chiral quaternary center. Catalyzed by an Ir/f-ampha complex, cyclic α,α-disubstituted 1,3-diketones were hydrogenated, giving mono-reduced products with both high enantioselectivities and diastereoselectivities. In addition, CC and CC bonds could survive in this catalytic system. This method was applied in the preparation of (+)-estrone. No diols were observed in this chemical transformation. The enantiomeric and diastereomeric induction were achieved as a result of steric hindrance.