119756-31-9

Upstream product

• 119756-54-6 1-(2'-tetrahydropyranyloxy)cyclohexa-1,4-diene 
• 4203-50-3 2-phenoxytetrahydropyran 
• 110-87-2 3,4-dihydro-2H-pyran 

Downstream Products

• 119756-56-8 (1R,2R,3R,4R)-3-Amino-4-(tetrahydro-pyran-2-yloxy)-bicyclo[2.2.2]oct-5-ene-2-carboxylic acid methyl ester 
• 119756-33-1 4(SR)-<1'-(SR)-methoxycarbonyl-2-nitroethyl>cyclohex-2-enone 
• 119756-33-1 4(SR)-<1'-(RS)-methoxycarbonyl-2-nitroethyl>cyclohex-2-enone 

Relevant academic research and scientific papers

AN APPROACH TO THE SYNTHESIS OF GELSEMINE: THE INTRAMOLECULAR RAECTION OF AN ALLYLSILANE WITH AN ACYLIMINIUM ION FOR THE SYNTHESIS OF ONE OF THE QUATERNARY CENTRES

We describe an efficient synthesis (summarised in Schemes 8 and 10) of an advanced intermediate (34) suitable for the synthesis of gelsemine.The key steps in the synthesis are (i) the Diels-Alder reaction between 1-tetrahydropyranyloxycyclohexa-1,3-diene (10) and methyl β-nitroacrylate (11) giving an adduct (12), in which the chiral centre in the tetrahydropyranyl ring is produced substantially in only one sense, (ii) the rearrangement of a bicyclooctane (23) into a bicyclooctane (24), where control of which bridge migrates is achieved by a choice of the counterion in the Lewis acid, and (iii) the efficient formation of the quaternary centre by an intramolecular reaction between an allylsilane group and an acyliminium ion (33 -> 34).