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Microwave (MW) irradiation facilitated synthesis provides fast, safe, simple, and green reaction conditions. MW irradiation of 2-aminobenzophenones with heteroaromatic ketones afforded quinolines via Friedlander condensation in high yields with intact halogen substituents for further modifications. Dibenzo[b,f][1,5]diazocines were found as minor products and in some instances as the only products as the result of self-condensation of 2-aminobenzophenones. Different acid catalysts were found to affect these cyclization processes. Mini library of quinolines and dibenzo[b,f][1,5]diazocines were created in order to understand the substituents effect on the reaction. Resultant quinolines and dibenzo[b,f][1,5]diazocines are anticipated to serve as an interesting library for high throughput screening of various biological applications.

Microwave (MW) irradiation facilitated synthesis provides fast, safe, simple, and green reaction conditions. MW irradiation of 2-aminobenzophenones with heteroaromatic ketones afforded quinolines via Friedlander condensation in high yields with intact halogen substituents for further modifications. Dibenzo[b,f][1,5]diazocines were found as minor products and in some instances as the only products as the result of self-condensation of 2-aminobenzophenones. Different acid catalysts were found to affect these cyclization processes. Mini library of quinolines and dibenzo[b,f][1,5]diazocines were created in order to understand the substituents effect on the reaction. Resultant quinolines and dibenzo[b,f][1,5]diazocines are anticipated to serve as an interesting library for high throughput screening of various biological applications.

Tropane alkaloids have received a great deal of attention because of their remarkable pharmaceutical significance. Therefore a variety of synthetic approaches to tropane alkaloids have been investigated. Especially, a series of tropanes showed anticonvulsant activity against pentylenetetrazol-induced convulsions in mice and antiarrhythmic activity in rabbit previously treated with ouabain. *Corresponding Author. E-mail : As a part of a research program related to the synthetic study of pharmacologically interesting tropane compounds, we now report the synthesis of di-(N-tropinonyl)benzenes and di-(N-tropinonyl)alkanes in the reaction of phenylenediamines (or diaminoalkanes) with 2,5-dimethoxytetrahydrofuran, and acetonedicarboxylic acid at 0 C. Earlier we reported the synthesis of N-substituted nortropinones in the reaction of amines with 2,5-dimethoxytetrahydrofuran, and acetonedicarboxylic acid. A representative experimental procedure for the synthesis of 1,4-di-(8-azabicyclo[3,2,1]octan-3-onyl)benzene (7) is as follows: A mixture of 2,5-dimethoxytetrahydrofuran (6.6 g, 0.05 mol), acetonedicarboxylic acid (5.84 g, 0.04 mol), water (20 mL), and c-HCl (0.5 mL) was stirred for 30 min. p-Phenylenediamine (2.16 g, 0.02 mol) in water (10 mL) was added by using a dropping funnel at 0 C. After the reaction mixture was stirred under N2 at room temperature for 22 h, a crude brown solid was precipitated. The reaction mixture was diluted with water (20 mL) and neutralized with saturated NaHCO3 solution. The neutralized solution was extracted with dichloromethane (100 mL × 3). The organic layer was dried (Na2SO4), filtered and concentrated. The residue was chromatographed on a silica gel (n-hexane : ethyl acetate = 1 : 3, v/v) to yield 7 (4.47 g, 69%) as a brown crystalline solid. H-NMR showed a singlet at δ 4.49 for four protons of C1 and C5, a doublet at δ 1.78 for four protons of C6n and C7n, a doublet at δ 2.17 for four protons of C6x and C7x, a doublet at δ 2.22 (H-2(4)α, J = 3 Hz). for four protons of C2α and C4α, and a doublet at δ 2.70 (H-2(4)α, J = 10 Hz) for four protons of C2β and C4β. Aromatic protons were at δ 6.89 as a singlet.

Reissert compounds derived from α,β-unsaturated acid chlorides were prepared. The conjugate base obtained from these Reissert compounds exhibited the following carbanion reactions: 1) Alkylation, 2) Condensation with benzaldehyde, 3) Rearrangement to give dimeric compounds rather than simple rearranged compounds. In the case of alkylated isoquinoline Reissert compounds, the attempted rearrangement led to ring annellated amines.

A novel one-pot synthesis of angular polycyclic hydrocarbon ring systems is described. The method involves Ti(IV)-promoted aldol-type condensation of silyl enol ethers with 2-arylacetaldehydes with concurrent cyclization and double dehydration of the adducts. Dehydrogenation of the partially saturated polyarene products either catalytically over palladium or with quinone oxidants, such as DDQ, affords fully aromatic polycyclic hydrocarbons. Examples of the synthesis of various phenanthrene, chrysene, benz[a]anthracene, and benz[j]acephenanthrylene derivatives via this route are presented.

The tropane class of alkaloids has continued to elicit the unabated interests among organic chemists because of their pharmacological significance, and a great deal of efforts has been focused on the stereochemical synthetic methodologies. Cocaine, a notorious member of this alkaloidal family, is found in erythroxylon coca, indigenous to the higher elevations of peru. The natives of this region, descendants of the Incas, still chew the coca leaf for its stimulatory properties. In particular, a series of tropans showed anticonvulsant activity against pentylenetetrazolinduced convulsions in mice and antiarrhythmic activity in rabbit previously treated with ouabain. As a part of ongoing research for the pharmacologically interesting tropane compounds, herein we report a new synthetic conditions of corresponding 2-substituted 8-azabicyclo[3.2.1]octan-3-one, 3, by aldol condensation from 8substituted 8-azabicyclo[3.2.1]octan-3-one, 1. We already reported a synthesis of 2,4-disubstituted 8-azabicyclo[3.2.1]octan-3-one, 2, derived from the reaction of N-substituted 8azabicyclo[3.2.1]octan-3-one, 1, with aldehydes (R1CHO) in the presence of ethanol and aqueous 5 N NaOH. We also reported the synthesis of di-(N-tropinonyl)alkanes from the reaction of phenylenediamines (or diaminoalkanes) with 2,5-dimethoxytetrahydrofuran and acetonedicarboxylic acid. Then our attempt to prepare 2-substituted 8-azabicyclo[3.2.1]octan-3-one, 3, from 8-substituted 8-azabicyclo[3.2.1]octan-3-one, 1, was unsuccessful, under various reaction conditions: sodium hydride, sodium methoxide, or butyl lithium. But M. Majewski and R. Lazny reported that their synthesized compound, 2-benzylidene-8-methyl-8-azabicyclo[3.2.1]octan-3-one was done through three-step treatment of chiral lithium amide, Ac2O, and SiO2 (Scheme 1). In brief, as their synthetic method had three-step reactions and three times work-ups, it was so complicated. Recently, Peter A. Crooks et al. reported two-step synthesis by treatment of lithium diisopropylamide or lithium bis(trimethylsilyl)amide. In order to synthesize 2-substituted 8-azabicyclo[3.2.1]octan-3-one, 3, simply and efficiently, we conducted research on the effect of aqueous NaOH concentration variations (1 N, 0.5 N, 0.1 N, 0.02 N, or 0.01 N). Yield comparison of compound 3e according to concentration variation of aqueous NaOH solution is expressed in Table 1. In case of higher concentrations over aqueous 0.01 N NaOH solution, the ratio of 2,4-disubstituted 8-azabicyclo[3.2.1]octan-3-one, 2, was produced somewhat higher than that of 2-substituted 8-azabicyclo[3.2.1]octan-3-one, 3. Yield of 8-benzylidene-8-phenyl-8-azabicyclo[3.2.1]octan