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The Michael-type reaction of amines with diethyl ethoxymethylenmalonate (EMME) (I) is described.

N-Alkenyl and N-alkoxymethyl lactams are impervious to many reagents and are useful protecting groups for lactams. Conversion to the corresponding 2-ethoxy iminium salt and hydrolysis in neutral water removes the protecting group. Mild basification regenerates the lactam.

1-(Phenylthio)cyclopropylcarbinyl alcohols are converted to 2-alkyl-1, 1-di(phenylthio)cyclobutane derivatives upon treatment with 48% HBr and ZnBr2. Heating with copper triflate and Hunig's base gave 2-alkyl-1-(phenylthio)cyclobutenes which were pyrolyzed to 3-alkyl-2-di-(phenylthio)-1,3-butadienes in moderate to good yield.

Glutamic acid is readily converted into N-butenyl-2-pyrrolidi-none-5-carboxaldehyde. The novel butenyl protecting group allows the synthesis of this aldehyde which can be olefinated using standard Wittig methodology.

2,4,6-Trimethylcyclohexa-2,4-dien-1-one derivatives undergo ring cleavage to furnish amides on irradiation with visible light in the presence of various amines. Seven different amides containing a substituted diene moiety were synthesized in 87–95% yield.

The reaction rate of Knoevenagel condensation can be dramatically enhanced by irradiating the reaction mixture containing an aldehyde, diethyl malonate, P2O5, piperidine, and chlorobenzene with a commercial microwave oven. Six Knoevenagel condensation products were synthesized within 5–15 min in good yields.

In an attempt to examine the role of the N(1)-alkyl or -aryl moiety of the quinolone antibacterials, several quinone methides such as perinaphthindenone carboxylates ( 6 ) were synthesized as 1-carba(sp2) analogues of the quinolone structure, and found to have no antibacterial activity. These results together with literature information are interpreted as the necessity of at least one nitrogen atom at the position of 1, 3, 4a, 6 or 8 in the quinolone-like skeleton for the antibacterial activities.

The reaction rate of Knoevenagel condensation can be dramatically enhanced by irradiating the reaction mixture containing ethyl cyanoacetate, an aldehyde, P2O5, piperidine, and chlorobenzene with a commercial microwave oven. A number of Knoevenagel condensation products were prepared in good yields in very short reaction times (2-15min) under the microwave irradiation.

An improved Knoevenagel condensation of malonic acid and aldehydes can be achieved by microwave irradiation over alumina. A number of diacids were prepared in good yields in very short reaction times.

Diethyl ethoxymethylenemalonate (EMME) is unexpectedly converted into diethyl 2-(1,1 -dialkyl and diarylmethyl) malonate derivatives by a classical Grignard reaction. Addition of organocuprates to EMME gave diethyl 2-(l-ethoxyalkyl) malonate derivatives. The yields range from 42-63%.

A stable sulfone derivative of 2,4,6-trimethylcyclohexa-2,4-diene-1-one (7) undergoes facile ring cleavage under visible light to produce a ketene intermediate, which could be efficiently captured by amines to give amides even in the presence of competing nucleophiles such as water and ethanol.

Summary This presentation describes a fast and facile microwaveenhanced N -alkenylation synthesis between sulfur-contain-ing lactam and various aldehydes such as n -propanal, iso-propanal, n -butanal, n -hexanal, n -octanal and phenylacet-aldehyde in 32 to 86% yields. In order to explain the con-formational properties of E/Z isomers, we used the couplingconstant ( J ) of 1 H and 2-D NOESY NMR techniques. In allcases, E isomers were predominantly produced. We expectthese new N -alkenyl pyrrolidine-2-thiones to have interest-ing applications for the protection of functionalized thio-lactams. Consequently, we are currently expanding ourresults using the advantages of microwave irradiation. Experimental Section Pyrrolidin-2-one, Lawesson’s reagent, p -toluenesulfonicacid monohydrate (98.5%), bentonite, K 10, Al 2 O 3, n -pro-panal, isopropanal, n -butanal, n -hexanal, n -octanal andphenylacetaldehyde were purchased from Sigma-Aldrich(Korea) and used as received. Toluene, chlorobenzene and

Rapid and facile syntheses of N-alkenyl lactam series via condensation between lactams and a variety of aldehydes such as n-propanal, isobutanal, n-butanal, n-hexanal, n-octanal and phenylacetaldehyde were studied under microwave or conventional heating. Various solid catalysts and solvents were examined to maximize the yields of condensation reactions.

A minilibrary of 12 quinoline derivatives was synthesized in the presence of 0.1–0.5 equiv. of diphenylphosphate without any solvents. Each compound was obtained with high yield in 4 min of microwave irradiation.

Thiophenyl substituted cyclohexa-2,4-dien-1-ones were synthesized and photolyzed in the presence of various amines to afford the amides containing diene moeties via the ketene intermediate under visible light irradiation at 38 °C.

La reaction de bromo-1' propyl-1 cyclopropyl phenyl sulfures avec des cuprates (R 2 CuLi), donne des alkyl-1- ou aryl-1 butene-1yl phenyl sulfures (majoritairement) et des propenyl-1 cyclopropyl phenyl sulfures