Núria Casamitjana

Diels–Alder Reactions of 5,6-Dihydro-2(1H)-pyridones

Abstract The Diels–Alder reaction of achiral 5,6-dihydro-2(1H)-pyridones 12a,b and enantiopure 5,6-dihydro-2(1H)-pyridones 16a,b with a variety of diversely substituted buta-1,3-dienes under thermal or catalytic conditions, to give partially reduced isoquinolones 18–33 and 35–37, is reported.

A new synthesis of 5-phenylmorphans1,2

Abstract A new procedure for the synthesis of 2-azabicyclo- [3.3.1]nonanes by intramolecular cyclization of 4-acetonyl-2- piperidinecarbonitriles under acidic conditions is described. The procedure allows the preparation of the pharmacologically interesting 5-phenylmorphans and involves the initial formation of 4-acetonylidenepiperidine 4, conjugate addition of a diarylcuprate, and cyclization of the resulting 4-acetonylpiperidine by way of the corresponding 2-cyano derivative.

FUNCTIONALIZED 2‐AZABICYCLO(3.3.1)NONANES. IV. SYNTHESIS OF THE INDOLO(3.2‐F)MORPHAN SYSTEM

Abstract A short route to the 2-azabicyclo[3.3.1]nonan-7-one system is described. Condensation of 4-piperidones with diethyl 2-oxopropylphosphonate, followed by catalytic hydrogenation furnished the corresponding piperidylpropanones 6 which were cyclized with mercuric acetate in acetic acid to the target target bicyclic ketones 1 . The Fischer indole synthesis from 1 a afforded regioselectively the indole [3,2-f]morphan 2 , a new heteromorphan type.

Dimethyl(methylthio)sulfonium fluoroborate induced cyclization of dithioacetals upon 2,3-disubstituted indoles

Abstract Treatment of dithioacetals 1a–c, 3, and 4 with DMTSF accomplishes cyclization upon the indole 3-position to give the Strychnos -type pentacles 2a–c, 10, and 11 , respectively.

The Fischer indolization of 2-azabicyclo[3.3.1]nonan-7-ones. A new entry to the dasycarpidan ring system

Abstract The regloselectivity of the Fischer indole synthesis from 2-azabicyclo[3.3.1]nonan-7-ones 4b–d using three different acid catalysts is studied, an ethyl substituent at the 9-position promoting indolization upon the C-8 carbon.

Stereocontrolled access to dasycarpidan-type compounds and formal total synthesis of Strychnos indole alkaloids of the Strychnan-type

Abstract An efficient, stereocontrolled synthesis of the tetracyclic bases 1 and 2 by cyclization of the regioisomeric cyanopiperidines 4 and 5 , prepared from the common cis -3-ethyl-4-(2-indolylmethyl)piperidine intermediate 3 , is reported.

Functionalized 2-azabicyclo[3.3.1] nonanes. vii.: A new synthesis of 4-azatricyclo[5.2.2.04,8]undecan-11-one

Abstract An improved method for the synthesis of 4-azatricyclo [5.2.2.04,8] undecan-11-one (1) is reported. The synthesis involves hydrogenolysis of 8-hydroxyethyl-2-azabicyclo [3.3.1] nonan-7-one 3 followed by intramolecular alkylation of the resulting secondary amine 7. The required azabicyclic alcohol 3 was obtained by oxidative cyclization with mercuric acetate of the α-alkylated methyl 4-piperidineacetoacetate 5.

Stereocontrolled synthesis of 4- and 9-ethyl-2-azabicyclo[3.3.1]nonan-7-ones via 2-cyanopiperidines

Abstract A stereoselective synthesis of 4- and 9-ethyl substituted morphans from 4-acetonyl-3-ethylpiperidines, involving the acidic cyclization of the corresponding 2-cyanopiperidines, is reported.

Diels–Alder reactions of phenylglycinol-derived bicyclic lactams. Enantiodivergent synthesis of cis-hydroisoquinolines

Abstract The diastereomeric phenylglycinol-derived unsaturated δ-lactams trans-3 and cis-3 react with dienes with exo facial diastereoselectivity to give the corresponding tricyclic adducts, which were ultimately converted to enantiomeric cis-hydroisoquinolines.

Diels-Alder reactions of 5,6-dihydro-2(1H)-pyridones. Preparation of partially reduced cis-isoquinolones and cis-3,4-disubstituted piperidines

Abstract The Diels-Alder reactions of 5,6-dihydro-2(1 H )-pyridones with a variety of diversely substituted butadienes to give partially reduced isoquinolones is reported. Reductive ozonolysis of the resulting octahydroisoquinolones gave cis -3,4-disubstituted piperidines.