A simple and highly diastereoselective synthesis of a 1β-methylcarbapenem key intermediate by deallyloxycarbonylation using palladium complexes

Murayama, T.; Yoshida, Akifumi; Kobayashi, T.; Miura, Takashi

doi:10.1016/0040-4039(94)85196-4

Cited by 25 publications

(6 citation statements)

References 12 publications

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“…According to Miura's report, 17 tetronate 18 was treated with formic acid (2.0 equiv) in the presence of 5 mol% of Pd(OAc) 2 and 10 mol% of PPh 3 in THF at 60 °C for 12 hours (Scheme 8). However, decarboxylation did not proceed and the corresponding carboxylic acid was obtained quantitatively as determined by 1 H NMR of the crude reaction mixture.…”

Section: Paper Syn Thesismentioning

confidence: 99%

“…The solvents were removed in vacuo, and the obtained crude product was treated with N-methylmorpholine (18 μL, 0.16 mmol) in THF (1.5 mL) at room temperature for 3 h. After concentration in vacuo, the obtained crude product was purified by silica gel column chromatography (hexane/EtOAc, 9:1) to afford 16 (46.3 mg, 81%) as a yellow solid (mp 46-47 °C). T. Kurohara et al Difluoro-2-(2-isopropoxy-3,4-dioxocyclobut-1-enyl)acetate (17) This compound was synthesized using the above described procedure for the synthesis of 4. Semisquarate 17 (1.47g, 54% yield) was obtained as a yellow oil.…”

Section: Acetate (15)mentioning

confidence: 99%

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Synthesis of Alkoxycarbonyldifluoromethyl-Substituted Semisquarates and Their Transformations

et al. 2018

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A novel EtO2CCF2-substituted semisquarate is synthesized from diisopropyl squarate by selective 1,2-addition of the Reformatsky reagent derived from BrCF2CO2Et and subsequent rhenium-catalyzed allylic alcohol rearrangement. The compatibility of the highly reactive EtO2CCF2 group in ring transformations of the obtained semisquarate is investigated. Various EtO2CCF2-substituted, highly functionalized compounds, such as quinones, tetronates, cyclopentenones and a bicyclo-[3.2.0]heptenone, are successfully synthesized by ring transformations of the EtO2CCF2-substituted semisquarate. Also, an allylO2CCF2-substituted semisquarate is prepared and converted into the corresponding tetronate. Subsequent palladium-catalyzed deallylation followed by condensation of the resulting carboxylic acid with several amines under mild conditions affords the corresponding α,α-difluoroamides in good yields.

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Section: Paper Syn Thesismentioning

confidence: 99%

Section: Acetate (15)mentioning

confidence: 99%

Synthesis of Alkoxycarbonyldifluoromethyl-Substituted Semisquarates and Their Transformations

et al. 2018

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“…With the establishment of a method of producing 6 by Shih et al in 1984 [5], many research groups started studying highly stereoselective synthesis of 18 which The Merck group and ourselves reported on a highly diastereoselective alkylation at the C-4 position of 4acetoxyazetidin-2-one (17) [7,8]. Since then, effective and industrial ways to prepare 17 and 18 have been reported [42,43,44].…”

Section: The Synthesis Of β-Methylazetidin-2-onementioning

confidence: 99%

“…They also evaluated the urinary recovery of some prodrug esters of R-83201 (42) after oral administration in mice. Among them, two prodrug esters of 42, the pivaloyloxymethyl ester (13) and the 1-methylcyclohexylcarbonyloxymethyl ester (43), exhibited excellent urinary recoveries of 47% and 55%, respectively. The pharmacokinetics of these two compounds in dogs after oral administration were compared to find the best prodrug ester ( Table 2) [68].…”

Section: Cs-834 (13)mentioning

confidence: 99%

Current Status of Oral Carbapenem Development

Kumagai¹,

Tamai²,

Abé³

et al. 2002

CMCAIA

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Since the discovery of thienamycin (1) in 1976, many studies on the synthesis and structure-activity relationships of parenteral-use drugs have been done and several carbapenems, imipenem (2), panipenem (3), and meropenem (7), have been marketed. The development of oral carbapenems, however, is a fairly slow process because carbapenems are considered unstable in the stomach and intestine. Recently, several orally active carbapenems without stability problems have been developed as prodrug esters or prodrug peptides, including GV-118819 (12), CS-834 (13), L-084 (14), DZ-2640 (15), and peptidic derivatives of CL 191,121 (16). The active forms (35), (41), (44), (45), (16) of these prodrugs exhibited potent and well balanced antibacterial activities as well as resistance to renal dehydropeptidase-I. The pharmacokinetic parameters of compounds (12), (13), (14), and (15) after oral administration to healthy volunteers were reported. The half-life (t 1/2) of GV-118819 (12) was longer than that of the other compounds, while the Cmax, AUC and urinary excretion rate of L-084 (14) were higher than those of the others. In this review, the synthesis, chemical and biological properties, and pharmacokinetics of these oral carbapenems are described.

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“…26) As an application, reaction of the diallyl malonate attached to β-lactam 111 proceeded stereoselectively to give the monocarboxylic acid with the β-oriented methyl group 112. 27) γ-Methylene-γ-butyrolactone 116 was prepared in one-pot in 81% yield from diallyl alkyl(2-propynyl)malonate 113 by palladium-catalyzed cyclization and hydrogenolysis with formic acid. 28) In this case, after oxidative addition, intramolecular oxypalladation of the triple bond in the intermediate 114 takes place to afford the (π -allylpalladium)alkenyllactone 115.…”

Section: )19)mentioning

confidence: 99%

Development of .BETA.-keto ester and malonate chemistry Palladium-catalyzed new reactions of their allylic esters

Tsuji

2004

Proceedings of the Japan Academy. Ser. B: Physical and Biologic

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Introduction.Palladium is now regarded as the most versatile metal among a number of transition metals used for organic synthesis.1) We started research on organopalladium chemistry in early 1960s, and discovered carbon-carbon bond formation by using palladium complexes for the first time. Since then we have carried out extensive studies on organopalladium. One topic of these studies is palladium-catalyzed reaction of allylic compounds via π-allylpalladium complexes. Among a number of new catalytic reactions discovered in this area, synthetically useful catalytic reactions of allyl β-keto carboxylates and malonates via palladium enolates are summarized in this review. The first palladium-mediated carbon-carbon bond formation. At first we investigated the possibility of carbon-carbon bond formation by using palladium complexes. When we treated the stable PdCl 2 complex of cyclooctadiene (COD) 1 with diethyl malonate in ether in the presence of sodium carbonate at room temperature, a facile carbopalladation occurred to give the new stable complex 2. This reaction is the first example of carbopalladation of an alkene in palladium chemistry, resulting in the carbon-carbon bond formation. The palladium-carbon σ-bond in the complex 2 is stabilized by coordination of π-olefin bond. By the treatment of the complex 2 with a base, malonate anion was generated and attacked the palladium-carbon bond, affording the bicyclo[6. Abstract: During extensive studies on π-allylpalladium chemistry, we have developed classical β-keto ester and malonate chemistry to a new generation by discovering a variety of palladium-catalyzed reactions of their allylic esters. Palladium enolates are generated from allyl β-keto esters after decarboxylation and undergo the following transformations; a) reductive elimination to provide α-allyl ketones, b) elimination of β-hydrogen to give α, β-unsaturated ketones, c) formation of α-methylene ketones, d) hydrogenolysis to give ketones, e) aldol condensation, and f) Michael addition. Allyl malonates and cyanoacetes undergo similar reactions. Results of these studies, including several applications carried out by other researchers are summarized.

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A simple and highly diastereoselective synthesis of a 1β-methylcarbapenem key intermediate by deallyloxycarbonylation using palladium complexes

Cited by 25 publications

References 12 publications

Synthesis of Alkoxycarbonyldifluoromethyl-Substituted Semisquarates and Their Transformations

Synthesis of Alkoxycarbonyldifluoromethyl-Substituted Semisquarates and Their Transformations

Current Status of Oral Carbapenem Development

Development of .BETA.-keto ester and malonate chemistry Palladium-catalyzed new reactions of their allylic esters

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