This invention relates to a process for the epoxidation of a tetrasubstituted alkene such as terpinolene to the corresponding epoxide such as terpinolene epoxide by reacting the tetrasubstituted alkene with peracetic acid prepared in situ from acetic anhydride and hydrogen peroxide in the presence of at least one buffering agent. Further, the invention relates to the use of an oxidizing agent comprising hydrogen peroxide and acetic anhydride for the in-situ epoxidation of a tetrasubstituted alkene.

This invention relates to a process for the epoxidation of a tetrasubstituted alkene such as terpinolene to the corresponding epoxide such as terpinolene epoxide by reacting the tetrasubstituted alkene with peracetic acid prepared in situ from acetic anhydride and hydrogen peroxide in the presence of at least one buffering agent. Further, the invention relates to the use of an oxidizing agent comprising hydrogen peroxide and acetic anhydride for the in-situ epoxidation of a tetrasubstituted alkene.

The present invention relates to a process for preparing an olefin oxide from a reaction mixture stream in an epoxidation reactor R, wherein R contains z active reaction tubes T(i) arranged in parallel, z?2, i=1 . . . z, wherein each T(i) comprises a reaction zone Z(i) comprising a heterogeneous epoxidation catalyst, said reaction mixture stream comprising x components C(j), x?3, j=1 . . . x, the process comprising (i) providing m educt streams E(k), m?1, k=1 . . . m, wherein each E(k) exhibits a mass flow rate F.sub.E(k) and comprises y components C(j), y=1 . . . x, wherein a given component C(j) is contained in at least one E(k); (ii) dividing each E(k) into n educt substreams S(k,i), n?z, each S(k,i) exhibiting a mass flow rate F.sub.s(k,i), wherein to at least one E(k), the inequality (1) applies: Formulas (1), (2), (3), (iii) providing n reaction mixtures streams M(i) comprising the x components C(j), said providing comprising, for each i, either combining and admixing the n educt substreams S(k,i) obtaining the n reaction mixtures M(i) if m>1, or passing on the n educt substreams S(k,i) as the n reaction mixtures M(i) if m=1; (iv) feeding each M(i) obtained according to (iii) into Z(i) and contacting each M(i) in Z(i) with the epoxidation catalyst under epoxidation reaction conditions; wherein the x components C(j) comprise hydrogen peroxide, an organic solvent, and the olefin. The present invention further relates to an olefin oxide obtained or obtainable from said process.

An intermediate compound is prepared and used for the synthesis of halichondrin B, eribulin or an analog thereof, particularly a structural fragment C27-C35 thereof. The starting materials of the synthetic route are readily available, and the optical purity of the starting materials can be ensured, so that the optical purity of the structural fragment C27-C35 in halichondrin B, eribulin or the analog thereof is ensured. Steps for constructing a chiral center of the structural fragment C27-C35 feature higher diastereoselectivity and yield, in particular preparation methods of compounds of formulae (X), (XI), (XVI) and (XV). By-products of partial reactions can be removed only by recrystallization, which results in easy purification and significant reduce in cost.

An intermediate compound is prepared and used for the synthesis of halichondrin B, eribulin or an analog thereof, particularly a structural fragment C27-C35 thereof. The starting materials of the synthetic route are readily available, and the optical purity of the starting materials can be ensured, so that the optical purity of the structural fragment C27-C35 in halichondrin B, eribulin or the analog thereof is ensured. Steps for constructing a chiral center of the structural fragment C27-C35 feature higher diastereoselectivity and yield, in particular preparation methods of compounds of formulae (X), (XI), (XVI) and (XV). By-products of partial reactions can be removed only by recrystallization, which results in easy purification and significant reduce in cost.

Disclosed herein is a process for purifying propylene oxide, including the steps of: (i) providing a stream S0 containing propylene oxide, acetonitrile, water, and an organic compound containing a carbonyl group C(O); and (ii) separating propylene oxide from the stream S0 by subjecting the stream S0 to distillation conditions in a distillation column to obtain a gaseous top stream S1c which is enriched in propylene oxide compared to the stream S0, a liquid bottoms stream S1a which is enriched in acetonitrile and water compared to the stream S0, and a side stream S1b containing propylene oxide which is enriched in the carbonyl compound compared to the stream S0.

Disclosed herein is a process for purifying propylene oxide, including the steps of: (i) providing a stream S0 containing propylene oxide, acetonitrile, water, and an organic compound containing a carbonyl group C(O); and (ii) separating propylene oxide from the stream S0 by subjecting the stream S0 to distillation conditions in a distillation column to obtain a gaseous top stream S1c which is enriched in propylene oxide compared to the stream S0, a liquid bottoms stream S1a which is enriched in acetonitrile and water compared to the stream S0, and a side stream S1b containing propylene oxide which is enriched in the carbonyl compound compared to the stream S0.

The present invention relates to a process for the preparation of terpinolene epoxide by epoxidation of terpinolene.

The present invention relates to a process for the preparation of terpinolene epoxide by epoxidation of terpinolene.

Disclosed is a propylene direct oxidation reaction catalyst capable of preparing a propylene oxide from propylene and oxygen at a higher yield than catalysts prepared by conventional methods, by applying a specific transition metal oxide promoter in preparation of a catalyst containing silver, a transition metal oxide promoter and a carrier through a slurry process. The present invention provides a propylene direct oxidation reaction catalyst, which is a supported silver catalyst used for preparing a propylene oxide from the propylene direct oxidation reaction, the catalyst including a molybdenum oxide and a tungsten oxide as a catalyst promoter.