9003-19-4Relevant articles and documents
Method for producing vinyl ether
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Paragraph 0038-0073, (2020/07/15)
The invention relates to a method for producing vinyl ether. The method comprises the following steps: (A) reacting excessive alcohol with acetaldehyde, and carrying out a continuous acetalation reaction by using immobilized superacid as a catalyst to obtain a first mixture; (B) carrying out oil-water separation and adsorption dehydration on the first mixture to obtain a second mixture; (C) carrying out acetal catalytic decomposition on the second mixture under the catalysis of a high-efficiency catalyst to obtain a third mixture; (D) rectifying the third mixture, and washing with water to obtain a vinyl ether product. According to the method, the high-temperature heating process of acetal is avoided, and the safety risk of operation is reduced; and an efficient acetal decomposition catalyst is adopted, and an acetal decomposition reaction is carried out at a low temperature, so that side reactions are few, and the selectivity of a main product is improved.
Waste-free technology for N-methylmorpholine synthesis
Markosyan,Baghdasaryan,Hovhannisyan,Attaryan,Hasratyan
, p. 845 - 847 (2014/02/14)
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Structural analogues of vitamin D
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, (2008/06/13)
PCT No. PCT/EP94/02294 Sec. 371 Date Jun. 28, 1996 Sec. 102(e) Date Jun. 28, 1996 PCT Filed Jul. 7, 1994 PCT Pub. No. WO95/01960 PCT Pub. Date Jan. 19, 1995The present invention relates to analogues of vitamin D, which lack the combined presence of the trans-fused six-membered C-ring and of five-membered D-ring, but still possess a central part consisting of a substituted chain of five atoms, atoms which correspond to positions 8, 14, 13, 17 and 20 of vitamin D, and at the ends of which are connected, at position 20 a structural moiety representing part of the side-chain of vitamin D or of an analogue of vitamin D, and at position 8 the DELTA (5,7)-diene moiety connected to the A-ring of the active 1-alpha-hydroxy metabolite or of an established vitamin D analogue, to their preparation process, to preparation intermediates, to pharmaceutical preparations comprising these compounds and to their use in medicine.