929189-24-2

Upstream product

• 220956-32-1 3,4-dimethoxy-2-(methoxymethoxy)methylphenylboronic acid 
• 220956-31-0 1-bromo-3,4-dimethoxy-2-((methoxymethoxy)methyl)benzene 
• 107290-27-7 (6-bromo-2,3-dimethoxyphenyl)methanol 
• 5653-67-8 2,3-dimethoxybenzyl alcohol 

Downstream Products

• 929189-25-3 benzyl (5S,6R)-6-[2-(hydroxymethyl)-3,4-dimethoxyphenyl]-5,6-dihydronaphtho[2,3-d][1,3]dioxol-5-ylcarbamate 
• 476-33-5 (4bR,5S,11bS)-1,2-dimethoxy-12-methyl-4b,5,6,11b,12,13-hexahydro[1,3]benzodioxolo[5,6-c]phenanthridin-5-ol 
• 929189-28-6 benzyl (4bR,4cR,5aS,10bS)-1,2-dimethoxy-4b,5a,10b,12-tetrahydro[1,3]benzodioxolo[5,6-c]oxireno[a]phenanthridine-11(4cH)-carboxylate 
• 929189-27-5 benzyl (4bR,5S,6S,11bS)-5-bromo-6-hydroxy-1,2-dimethoxy-4b,6,11b,13-tetrahydro[1,3]benzodioxolo[5,6-c]phenanthridine-12(5H)-carboxylate 
• 929189-26-4 benzyl (4bR,11bS)-1,2-dimethoxy-4b,13-dihydro[1,3]benzodioxolo[5,6-c]phenanthridine-12(11bH)-carboxylate 

Relevant academic research and scientific papers

Enantioselective total synthesis of (+)-homochelidonine by a Pd II-catalyzed asymmetric ring-opening reaction of a meso-azabicyclic alkene with an aryl boronic acid

(Chemical Equation Presented) An efficient and highly convergent enantioselective synthesis of (+)-homochelidonine has been achieved (see scheme; Cbz = benzyloxycarbonyl, MOM = methoxymethyl) and relied on a new and powerful desymmetrizing ring-opening reaction of a meso-azabicycle with an aryl boronic acid. The route should allow access to other hexahydrobenzo[c]phenanthridine alkaloids.

Concise enantioselective total syntheses of (+)-homochelidonine, (+)-chelamidine, (+)-chelidonine, (+)-chelamine and (+)-norchelidonine by a PdII-catalyzed ring-opening strategy

New enantioselective syntheses of the B/C hexahydrobenzo[c]phenanthridine alkaloids (+)-homochelidonine, (+)-chelamidine, (+)-chelidonine, (+)-chelamine, and (+)-norchelidonine are described. Our rapid and convergent route to this class of natural products involved the development and application of a Pd II-catalyzed asymmetric ring-opening reaction of a mesoazabicyclic alkene with an aryl boronic acid as the key step. By screening a variety of functionalized ortho-substituted aryl boronic acids, chiral ligands and reaction conditions we were able to prepare the requisite cis-1-amino-2- aryldihydronaphthalenes in high yield and in up to 90% ee. Early attempts to complete the synthesis of (+)-homochelidonine using an N-Boc azabicyclic alkene are described in full. The successful route required a protecting group alteration followed by B ring for-mation and then stereoselective installation of the C-11 syn-hydroxy group by regioselective epoxide ring-opening using a hydride source. Ring-opening of the same epoxide intermediate with water ultimately led to the synthesis of (+)-chelamidine. The same strategy was then used to synthesize the other structurally similar B/C hexahydrobenzo[c] phenanthridine alkaloids, (+)-chelidonine, (+)-chelamidine, and (+)norchelidonine.