Miwako Mori

An improved 1,3-diene synthesis from alkyne and ethylene using cross-enyne metathesis

Abstract Synthesis of 1,3-diene from alkyne and ethylene (1 atm) was improved using ruthenium carbene complex 1b having heterocyclic carbene as a ligand. In this reaction, the heteroatom at the propargylic position was not required, although the reaction of alkyne with the first-generation ruthenium carbene complex 1a was affected by the substituent at the propargylic position. Various 1,3-dienes could be synthesized from alkynes and ethylene.

New synthesis of heterocycles by use of palladium catalyzed cycli zation of α-haloamide with internal double bond

Abstract α-Haloamide having internal double bond was allowed to react with a catalytic amount of Pd(PPh 3 ) 4 in the presence of base to produce a cyclized product in a fairly good yield possibly through the intermediate of -alkylmetal complex. By use of this method, five and six membered lactams, pyrrolizidine and quinolizidine derivatives were synthesized in fairly good yields.

New synthesis of β-lactams

Abstract α-Methylene-β-lactams 3 were synthesized from the various 2-bromoallylamine derivatives 2 using a catalytic amount of Pd(OAc) 2 or PD(acac) 2 and PPh 3 , under 1–4 atom pressure of CO in good yields. Similarly, α-alkylidene-β-lactams 20 were synthesized from 3-alkyl-2-bromoallylamines 19 , which were easily prepared from the olefins 14 , in the same manner.

FIXATION OF ATMOSPHERIC NITROGEN : SYNTHESIS OF HETEROCYCLES WITH ATMOSPHERIC NITROGEN AS THE NITROGEN SOURCE

Dry air is the source of molecular nitrogen for reactions with TiL4 , Li, and TMSCl (L = Cl, OiPr; TMS = trimethylsilyl). The nitrogen-titanium complexes thus prepared can be used to synthesize indoles, pyrroles, and lactams from carbonyl compounds. Applying this method to 1 provides access to 2, the key compound in the synthesis of (±)-lycopodine.

Nickel-catalyzed regio- and stereoselective synthesis of homoallylic alcohol derivatives from dienes and aldehydes

Abstract The reaction of 1,3-Dienes and aldehydes in the presence of Et 3 SiH using a catalytic amount of Ni(cod) 2 and PPh 3 gave homoallylic alcohol derivatives in a regio- and stereoselective manner.

Preparation and synthetic use of the zerovalent nickel complex by electrochemical reduction

Abstract The generation of Ni(PPh 3 ) 4 by electrochemical reduction was carried out in a divided cell containing NiCl 2 (PPh 3 ) 4 , PPh 3 and n-Bu 4 NBr in DMF with a lead plate as cathode and a platinum plate as anode under the stream of argon at 60°. Using this Ni(PPh 3 ) 4 , biphenyls and the heterocyclic compounds were synthesized in fairly good yields.

Synthesis of different ring-size heterocycles from the same propargyl alcohol derivative by ligand effect on Pd(0)

Abstract The type of ligand on an allenylpalladium complex, which was prepared from propargyl alcohol derivative and Pd(0), plays an important role in determination of the ring size of the cyclized compound. An intermediary palladium complex bearing a monodentate ligand gave a cyclized compound via palladacycle, while that bearing a bidentate ligand gave one-carbon elongated cyclized compound via a η 3 -propargylpalladium complex.

New synthesis of 4-acetoxy-2-azetidinones by use of electrochemical oxidation

Abstract 4-Acetoxy-2-azetidinone was synthesized from 4-carboxy-2-azetidinone by Kolbe-type electrolysis. Optically pure 4-acetoxy-3-[1-(t-butyldimethylsiloxy)ethyl]-2-azetidinone, which is an important intermediate for the synthesis of thienamycin, and (+)-PS-5 were synthesized by use of this method.

Cyclization of α-haloamide with internal double bond by use of the low-valent metal complex

Abstract The α-haloamide having internal double bond was allowed to react with a catalytic amount of Pd(PPh 3 ) 4 in the presence of proton sponge to produce a cyclized product in a fairly good yield possibly through the intermediation of σ-alkylmetal complex although it was not isolated.

Synthesis of 3-alkoxycarbonyl-1β-methylcarbapenem using palladium-catalyzed amidation of vinyl halide

Abstract 3-Alkoxycarbonyl-1β-methylcarbapenem could be synthesized using a palladium-catalyzed CN bond-forming reaction. In this reaction, the use of Pd(OAc)2 and DPEphos gave a good result, and generation of Pd(0) in the absence of a base is necessary to increase the yield.