36551-90-3

Upstream product

• 39746-31-1 10-oxatriacyclo<4.3.1.0>decan-2-one 
• 3296-46-6 4-(2-oxocyclopentyl)butanoic acid 
• 108-24-7 acetic anhydride 
• 1314042-97-1 C₁₁H₁₄O₄ 
• 1314043-02-1 C₁₄H₂₂O₃ 
• 1314042-95-9 C₁₃H₂₀O₅ 
• 41975-67-1 1-allyl-2-oxo-cyclopentanecarboxylic acid ethyl ester 
• 611-10-9 2-ethoxycarbonyl-1-cyclopentanone 
• 156991-64-9 ethyl (R)-1-(prop-2-enyl)-2-oxocyclopentanecarboxylate 
• 21932-24-1 (1R,5R,6R)-spiro<4.4>-nonane-1,6-diol 
• 1314042-96-0 C₁₃H₂₀O₅ 
• 1314042-98-2 C₁₁H₁₄O₄ 
• 196716-59-3 (1S,2S)-(+)-ethyl 1-allyl-2-hydroxycyclopentanecarboxylate 

Downstream Products

• 852999-33-8 6-(o-methoxyphenyl)-1-trifluoromethanesulphonyloxy-spiro[4,4]nona-1,6-diene 
• 36551-90-3 (+)-1,6-spiro<4.4>nonanedione 
• 95517-39-8 (R)-3,3,3-Trifluoro-2-methoxy-2-phenyl-propionic acid 6-((R)-3,3,3-trifluoro-2-methoxy-2-phenyl-propionyloxy)-spiro[4.4]non-1-yl ester 
• 39170-75-7 (-)-(1R,6R)-trans,trans-Spiro<4,4>nonan-1,6-diol-bis-<4-methyl-phenyl-thion-kohlensaeureester> 
• 241820-33-7 1,6-bis(phenyl)-spiro<4,4>nona-1,6-diene 

Relevant academic research and scientific papers

Catalytic enantioselective synthesis of carbocyclic and heterocyclic spiranes: Via a decarboxylative aldol cyclization

The synthesis of a variety of enantioenriched 1,3-diketospiranes from the corresponding racemic allyl β-ketoesters via an interrupted asymmetric allylic alkylation is disclosed. Substrates possessing pendant aldehydes undergo decarboxylative enolate forma

Catalytic enantioselective synthesis of chiral spirocyclic 1,3-diketones: Via organo-cation catalysis

An SPA-triazolium bromide-catalyzed transannular C-acylation of enol lactones is presented. This methodology provides convenient access to a range of enantioenriched spirocyclic 1,3-diketones in moderate to high yields and enantioselectivities and features a broad substrate scope in terms of enol lactones. The catalytic capability of this triazolium salt catalyst is also demonstrated in this enantioselective transformation, which could inspire its further application. This journal is

Synthesis of spiro-ring bis-boron catalyst and application thereof in hydrogenation reaction

The invention relates to a synthesis of spiro-ring diene compound with C2 symmetry, and a a series of chirality spiro-ring bis-boron catalysts prepared by virtue of the reaction of the spiro-ring diene compound and boron hydrides. The spiro-ring bis-boron catalysts have high activity and enantioselectivity in the asymmetric hydrogenation reaction of quinoline compounds, and belong to the technicalfield of application. By adopting the synthesis of spiro-ring bis-boron catalyst and the application thereof in hydrogenation reaction, the problems of the traditional quinoline asymmetric hydrogenation reaction method that precious metal catalysts are used and the functional groups are poor in tolerance can be mainly solved, the nonmetal catalytic quinoline asymmetric hydrogenation reaction canbe realized, the reaction substrate range is wide, and the functional group tolerance is high. The synthesis of spiro-ring bis-boron catalyst and the application thereof in hydrogenation reaction areused in the medicine research and chemical production.

Spiro-Bicyclic Bisborane Catalysts for Metal-Free Chemoselective and Enantioselective Hydrogenation of Quinolines

A new series of spiro-bicyclic bisborane catalysts has been prepared by means of hydroboration reactions of C2-symmetric spiro-bicyclic dienes with HB(C6F5)2 and HB(p-C6F4H)2. When used for hydrogenation of quinolines, these catalysts give excellent yields and enantiomeric excesses, and show turnover numbers of up to 460. The most attractive feature of these metal-free hydrogenation reactions was the broad functional-group tolerance, making this method complementary to existing methods for quinoline hydrogenation.

A practical asymmetric synthesis of enantiopure spiro[4,4]nonane-1,6-dione

A practical asymmetric synthesis of enantiopure spiro[4,4]nonane-1,6-dione, a valuable precursor for chiral ligand development, is reported. This synthetic strategy includes a kinetic resolution of the readily synthesized ketone precursor with a chiral qu

Promoter-dependent course of the Beckmann rearrangement of stereoisomeric spiro[4.4]nonane-1,6-dione monoximes

(Chemical Equation Presented) Activation of the Beckmann rearrangement of the enantiopure spirocyclic keto oximes (-)-9 and (-)-12 has been initiated with four acidic promoters. In two cases (PPE and PPSE), concerted 1,2 shift of the anti carbon operates

An efficient synthesis and resolution of (±)-cis,cis-spiro[4.4]nonane- 1,6-diol

A four step highly stereoselective synthesis of (±)-cis,cis- spiro[4.4]nonane-1,6-diol (4) in 55% overall yield is described in detail beginning with ethyl 2-oxocyclopentanecarboxylate. A new resolution of diol (±)-4 using (1R)-(+)-camphor is also reported.

Enantio- and Diastereo-selective Synthesis of Spirocyclic Compounds

Spirocyclic diones such as (R)-spirononane-1,6-dione 1a, (R)-spirodecane-1,6-dione 1b and (R)-spiroundecane-1,7-dione 1c, and the corresponding cis,cis-diols 2a-c have been enantio- and diastereo-selectively synthesized by asymmetric alkyla

An Improved Synthesis and Resolution of (+/-)-cis,cis-SpiroNoname-1,6-Diol

(+/-)-cis,cis-Spirononane-1,6-diol (2) is synthesized stereoselectively in four steps (51percent) beginning with ethyl 2-oxocyclopentanecarboxylate.An improved resolution of diol 2 is described by preparing diastereomeric ketals of (1R)-(+)-camphor.The relative stereochemistry of cis,cis-diol 2 is unambiguously assigned via an X-ray crystal structure of the bis-(p-nitrobenzoate) derivative.

Microbial stereodifferentiating reduction of 1,6-spiro[4.4]nonanedione, a gyrochiral diketone with two homotopic carbonyl groups

After a preliminary incubation of 1-spiro[4.4]nonanone (14) with Curvularia lunata, affording (+)-(1S)-alcohol 15 with 100% optical purity, (±)-1,6-spiro[4.4]nonanedione (8) was incubated with C. lunata for 8 h at 30°C to yield a 34:30:36 mixture of (-)-(5S)-8, (+)-trans-(5R,6S)-ketol 9, and (-)-cis-(5R,6R)-ketol 10 with respective 82%, 76%, and 6% optical purities. Incubation of (±)-trans-6-hydroxyspiro[4.4]nonan-1-one (9) furnished a metabolite mixture containing (-)-trans-(5S,6R)-9, (+)-trans,trans-(1S,5R,6S)-diol 11, and (+)-cis,trans-(1R,5S,6S)-diol 12 with respective 56%, 80%, and 73% optical purities. Although a modified quadrant rule for C1 ketones could explain these microbial stereoselectivities, serious perturbing effects from the unique spirane framework and the neighboring functional groups were observed.