Robert E. Harmon

The structure of cis and trans lsomers of 1-(p-Bromobenzylidene)-2-indanone

Abstract In this communication we wish to report an interesting case of the isolation and characterization of the cis and trans isomers of 1-(p-bromobenzylidene)-2-indanone and their ketals. Prior to this work, Hoogstreen and Trenner2 had reported on the cis and trans isomers of 1-(p-chlorobenzylidene)-2-methyl-5-methoxyindenylacetic acid. The condensation of 2-(N-morpholinyl)-indene (1, prepared by the reaction of 2-indanone3 and morpholine) with P-bromobenzaldehyde was conducted by refluxing them in the presence of acetic acid for 4 hours. Acid hydrolysis of the reaction mixture followed by dry column chrcmatography over sillica gel using a fraction collector afforded two iscmeric monobenzylidenes, compounds 2(36.6%, mp 110–111°)and 3(1.3%, mp 115–116°) and a dibenylidene, compound 4 (8.7%, mp 205°). The relative rations of the mono- and dibenzylidenes seemed to depend on the reaction conditions. Higher yields of the monobenzylidenes 2 and 3 were obtained by conducting the reaction in the presence of UV...

Supra-additive toxic interaction of nicotine with antihistamines, and enhancement by the proconvulsant pentylenetetrazole

Antihistamines are being increasingly administered in combination with various other agents, with adverse drug reactions the frequent result. The present study consisted of two experiments. Experiment 1 examined the toxicological response of rats to nicotine tartrate (0.0, 2.0, 4.0, and 8.0 mg/kg) in combination with either of two H1-histamine receptor antagonists, the ethylene diamine tripelennamine HCl (0.0, 16.0, 32.0, and 64.0 mg/kg) or the aminoethyl ether diphenhydramine HCl (0.0, 32.0, 64.0, and 96.0 mg/kg). Adult female rats received intraperitoneal injections when housed 12 per cage and toxicological response (number dead per group) was assessed 24 hours post-treatment. The results showed that over the dose ranges employed, and when given alone, nicotine was completely non-lethal, tripelennamine was virtually non-lethal and diphenhydramine was toxic only at the highest dose (5 of 12, at 96.0 mg/kg). However, when nicotine and the antihistamines were delivered in combinations, the toxicological response was markedly altered. Tripelennamine in combination with nicotine yielded supra-additive interaction, with the degree of potentiation being a simple linear function of nicotine within each dose of tripelennamine. The interaction between nicotine and diphenhydramine was more complicated, with certain dose combinations yielding supra-additivity, yet with others yielding antagonism. It was suggested that seizure-precipitated cardiopulmonary collapse was the immediate cause of death, plausibly mediated by central mechanisms. As such, Experiment 2 examined the influence of adding the proconvulsant pentylenetetrazole (PTZ) (0.0, 10.0, and 20.0 mg/kg) to nicotine (0.0, 2.0, 4.0, and 8.0 mg/kg)-tripelennamine (0.0 and 32.0 mg/kg) combination treatments. Effects were assessed both at 1.0 and 24.0 hours post-injection.(ABSTRACT TRUNCATED AT 250 WORDS)

Photoreduction of an α-Dichloroketone

Abstract In recent years, we have reported on the cycloaddition reactions of dichloroketene to diphenylfulvene1, diphenylbenzorulvene1, and indene2. Last year Kaplan and Hartwig3 published an interesting communication describing the photolysis of exo-3-chlorobicyclo [2.2.1] hept-5-en-2-one (1) to from endo-o-carbomethoxybicyclo [3.1.0] hex-2-ene (2) in a stereospecific manner.

Total synthesis of acephenanthren-5-one.

Acephenanthren-5-one, a key intermediate in the preparation of certain acephenanthrene amino-alcohols as potential antimalarials, has been synthesised in five stages from 1-methylphenanthrene.

Preparation and properties of some benzotropylium perchlorates

The syntheses of a variety of substituted benzotropylium perchlorates, 6,8-polymethylenebenzotropylium perchlorates, and 6,6′:8,8′-bispolymethylenedi(benzotropylium perchlorate)s are described. In addition, evidence for the existence of 1a,3-polymethylenebenzohomotropylium cations is presented. By n.m.r. spectroscopy it has been shown that the positive charge (or charges) in these benzotropylium ions is delocalized over both the six- and the seven-membered rings.

1,3-Dipolar additions of glycosyl azides to substituted acetylenes

The 1,3-dipolar additions of fully acetylated β-D-glycosyl azides to ynamines, ethoxyacetylene, and 1-ethylthio-2-phenylacetylene led to the formation of the corresponding N-glycosyl-2,3,4-triazoles.

Dichloroketen adducts of 6,6-diphenylfulvene and 8,8-diphenylbenzofulvene

The reaction of dichloroketen with 6,6-diphenylfulvene afforded a crystalline cycloadduct identified as cis-7,7-dichloro-4-diphenylmethylenebicyclo[3,2,0]hept-2-en-6-one by n.m.r. and chemical degradation studies. Similarly, the adduct obtained from dichloroketen and 8,8-diphenylbenzofulvene was shown to be cis-2,2-dichloro-2,2a,7,7a-tetrahydro-7-diphenylmethylene-1H-cyclobut[a]inden-1-one by n.m.r. analysis.

Reaction of dichloroketen with diphenylfulvene and diphenylbenzofulvene

The reactions of dichloroketen with diphenylfulvene and diphenylbenzofulvene afforded 1,2-mono-adducts whose structure and stereochemistry were proved by detailed n.m.r. analysis.

HOMOGENE KATALYTISCHE HYDRIERUNG ALPHA,BETA-UNGESAETTIGTER NITROVERBINDUNGEN MIT TRIARYLPHOSPHIN-KOMPLEXEN

Durch homogene Hydrierung uber den beiden Triarylrhodiumkomplexen (I) und (II) gelingt es, ungesattigte Nitroverbindungen, z.B. (III) und (V), ohne Veranderung der Nitrogruppe ausschlieslich an der Doppelbindung mit Ausbeuten von 84 und 90% zu (IV) und (VI) zu hydrieren.

Preparation of 2,7-polymethylenebis-4,5-benzotropylium perchlorates

The synthesis of 2,7-tetramethylene-4,5-bis-benzotropylium perchlorate, an interesting example of a compound containing two positive charges within the same molecule, has been accomplished.