201748-24-5

Upstream product

• 214477-57-3 (+)-(3R,4S)-4-<(S)-2,2-dimethyl-1,3-dioxolan-4-yl>-3-phenoxy-1-(2-propen-yl)-2-azetidinone 
• 701-99-5 Phenoxyacetyl chloride 
• 358973-81-6 Allyl-[1-((S)-2,2-dimethyl-[1,3]dioxolan-4-yl)-meth-(E)-ylidene]-amine 
• 214477-58-4 (3R,4S)-4-[(1S)-1,2-dihydroxyethyl]-3-phenoxy-1-allylazetidin-2-one 

Downstream Products

• 214477-33-5 cis-4-(1-hydroxy-3-(trimethylsilyl)-2-propynyl)-3-phenoxy-1-(2-propenyl)-2-azetidinone 
• 246031-50-5 (1S,2S,3R,7R)-9-Methyl-3-phenoxy-8-oxa-5,9-diaza-tricyclo[5.2.1.0^2,5]decan-4-one 
• 251480-01-0 (3R,4S)-4-[(R)-1-hydroxy-2-methylidene-3-oxobutyl]-3-phenoxy-1-(2-propenyl)-2-azetidinone 
• 277757-90-1 (3R,4S)-4-[(R)-1-hydroxy-3-butenyl]-3-phenoxy-1-(2-propenyl)-2-azetidinone 
• 331258-68-5 (3R,4S)-4-[(R)-2-carboxymethyl-1-hydroxy-2-propenyl]-3-phenoxy-1-(2-propenyl)-2-azetidinone 
• 663619-24-7 (3R,4S)-1-Allyl-4-((R)-1-hydroxy-3-phenyl-prop-2-ynyl)-3-phenoxy-azetidin-2-one 
• 663619-25-8 (3R,4S)-1-Allyl-4-((R)-1-hydroxy-3-trimethylsilanyl-prop-2-ynyl)-3-phenoxy-azetidin-2-one 
• 246031-62-9 (3R,5S,6S,7R)-3-Hydroxy-5-methylamino-7-phenoxy-1-aza-bicyclo[4.2.0]octan-8-one 
• 663619-41-8 (3R,4S)-1-Allyl-4-((S)-1-azido-3-trimethylsilanyl-prop-2-ynyl)-3-phenoxy-azetidin-2-one 

Relevant academic research and scientific papers

Asymmetric synthesis of 4-formyl-1-(ω-haloalkyl)-β-lactams and their transformation to functionalized piperazines and 1,4-diazepanes

Chiral piperazine and 1,4-diazepane annulated β-lactams, prepared from the corresponding (3R,4S)-4-imidoyl-1-(ω-haloalkyl)azetidin-2-ones through reduction with sodium borohydride in ethanol, were transformed into novel methyl (R)-alkoxy-[(S)-piperazin-2-yl]acetates and methyl (R)-alkoxy-[(S)-1,4-diazepan-2-yl]acetates upon treatment with hydrogen chloride in methanol. On the other hand, bromination of (3R,4R)-1-allyl-4-formyl-β- lactams and (3R,4S)-1-allyl-4-imidoyl-β-lactams in dichloromethane, followed by sodium borohydride reduction of the resulting dibrominated azetidin-2-ones in ethanol, did not afford the envisaged bicyclic β-lactams but unexpectedly furnished (3R,4S)-1-(2-bromo-2-propenyl)azetidin-2-ones instead.

Straightforward asymmetric entry to highly functionalized medium-sized rings fused to β-lactams via chemo- and stereocontrolled divergent radical cyclization of Baylis-Hillman adducts derived from 4-oxoazetidine-2-carbaldehydes

DABCO promoted reactions of various activated vinyl systems with optically pure 4-oxoazetidine-2-carbaldehydes 1 gave rise to Baylis - Hillman adducts 3 with excellent syn stereoselectivities, without detectable racemization. Products 3 are used for the asymmetric preparation of unusual 2-azetidinones fused to medium-sized rings via chemo- and stereocontrolled divergent radical cyclization. The formation of bicyclic β-lactams 4 - 6 could be rationalized through a tandem radical Michael addition/endo cyclization or a tandem radical addition/Michael addition, depending on the electronic nature of the radical promoter.

Stereoselective allylation of 4-oxoazetidine-2-carbaldehydes. Application to the stereocontrolled synthesis of fused tricyclic β-lactams via intramolecular Diels-Alder reaction of 2-azetidinone-tethered trienes

Allylation reactions of racemic and optically pure 4-oxoazetidine-2- carbaldehydes were investigated both under anhydrous conditions and in aqueous media. Different Lewis acid or metal mediators showed varied diastereoselectivities on product formation du

Rapid entry to enantiopure polycyclic β-lactams via intramolecular nitrone-alkene cycloaddition of 2-azetidinone-tethered alkenylaldehydes

New enantiomerically pure fused 2 or bridged 3 polycyclic β-lactam systems are regio- and stereoselectively prepared via intramolecular nitrone- alkene cycloaddition of 2-azetidinone-tethered alkenyl-aldehydes 1. The regioselectivity of the cycloaddition

Alkyne-Co2(CO)6 complexes in the synthesis of fused tricyclic β- lactam and azetidine systems

A synthetic approach to racemic and enantiomerically pure, fused tricyclic 2-azetidinones and azetidines has been developed by using a Pauson- Khand (P-K) reaction on monocyclic enyne-β-lactams as the key synthetic step. The access to cyclization precursors, monocyclic β-lactams 1-7, was achieved by Staudinger reaction of enyne imines 8 and 9 and D-glyceraldehyde imines 10 and (benzyloxy)- or phenoxyacetyl chlorides. Enyne imines 8 and 9 formed cis-2-azetidinones 1 and 2 having the required enyne moiety. cis-2- Azetidinones 11 were obtained as single diastereomers and transformed to enyne-2-azetidinones 3 and 5 by standard methodology. Alternatively, 4- formyl-2-azetidinones 14 were prepared by cyclization of p-anisyl glyoxal diimine and (benzyloxy)acetyl chloride and converted to racemic enyne-β- lactams 4 and 6 by standard reactions. Enyne-2-azetidinones 1-7 were reacted with Co2(Co)8 to quantitatively yield the corresponding alkyne-Co2(CO)6 complexes. Reaction of such complexes with different promoters, especially heat and TMANO, formed tricyclic 2-azetidinones 15-19 with the ring system fused to the C3-C4 and C4-N1 lactam bonds. Yields were usually high, and the processes were highly diastereoselective. The exceptions were enyne-2- azetidinones 2 and 3a bearing N-propargyl moieties. These products decomposed to mixtures of unidentifiable products. Inhibition of the amide resonance was postulated as responsible for the failure of β-lactams 2 and 3a to form tricyclic systems. In fact, the analogous enyne-azetidines 20a,b smoothly cyclized to form the corresponding tricyclic systems. This approach to tricyclic azetidines was extended to prepare different products. A new, unprecedented, N1-C2 bond breakage was also observed in the azetidine ring. The results described show that the P-K reaction is a suitable approach to tricyclic 2-azetidinones and azetidines. These are the first examples reported for a P-K reaction in with the enyne system is tethered to a strained heterocyclic four-membered ring.