Special Issue

Derek H. R. Barton's Special Issues, Vol. 28, No. 1, 1989

75 data found. 31 - 60 listedFirst Previous Next Last
Communication | Special issue | Vol 28, No. 1, 1989, pp. 143 - 146
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DOI: 10.3987/COM-88-S64
Alkylations of Heterocycles by Alkylmercurials

Glen A. Russell,* Deliang Guo, Woonphil Baik, and S. J. Herron

*Department of Chemistry, Iowa State University, Ames, Iowa 50011, U.S.A.


Alkylmercurials can participate in free radical chain reactions in which the alkyl group substitutes for hydrogen or halogen at a heterocyclic vinyl or aromatic carbon atom, adds in a conjugate manner to α,β-unsaturated lactones or lactams, or undergoes addition-elimination (cyclization) reactions leading to a new heterocyclic ring.

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Communication | Special issue | Vol 28, No. 1, 1989, pp. 147 - 150
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DOI: 10.3987/COM-88-S66
Reactions of the Pyrrolidine Dienamine of Pummere’s Ketone with Nitrosocarbonylmethane

Andrew A. Freer, Md. Azizul Islam, Gordon W. Kirby,* and Mohinder P. Mahajan

*Departmentof Chemistry, University of Glasgow, Joseph Black Building, Glasgow G12 8QQ Scotland, U.K.


The pyrrolidine dienamine (2) of Pummerer’s ketone (1) reacts with the dienophile nitrosocarbonylmethane to give a bridged onazine (9). The structure (9), incorporating 2 mol equiv. of the nitroso compound with reductive loss of 1 oxygen atom, has been determined by X-ray methods. Other products were the hydroxamic acid (6) and the acetamidoenone (7).

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Communication | Special issue | Vol 28, No. 1, 1989, pp. 151 - 156
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DOI: 10.3987/COM-88-S67
Gas Chromatography-Mass Spectrometry of Cyclic Boronate Derivatives of Some Alkaloid and Terpenoid Diols

Charles J. W. Brooks,* W. John Cole, and David J. Robins

*Departmentof Chemistry, University of Glasgow, Joseph Black Building, Glasgow G12 8QQ Scotland, U.K.


Cyclic ferroceneboronates of the alkaloidal diols retronecine, platynecine, rosmarinecine and swainsonine, and the bis-methaneboronate of aphidicolin are suitable derivatives for gas chromatography-mass spectrometry

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Communication | Special issue | Vol 28, No. 1, 1989, pp. 157 - 161
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DOI: 10.3987/COM-88-S70
Degradation and Manipulations of the Immunosuppressant FK506: Preparation of Potential Synthetic Intermediates

Robert S. Coleman and Samuel J. Danishefsky*

*Department of Chemistry, Yale University, P.O. Box 6666, New Haven, Connecticut 06511, U.S.A.


Degradation of the immunosuppressant FK506 is described.

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Communication | Special issue | Vol 28, No. 1, 1989, pp. 163 - 166
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DOI: 10.3987/COM-88-S71
Synthesis of 1-Substituted Derivatives of Codeine from 1-Bromocodeine via Palladium Catalysed Coupling Reactions

Stephen G. Davies* and Dirk Pyatt

*Dyson Perrins Laboratory, Oxford University , South Parks Road, Oxford OX1 3QY, U.K.


The 1-(methyl-β-propenoate), 1-β-styryl, 1-carboethoxy and 1-methyl derivatives of codeine have been prepared in good yields from 1-bromocodeine via palladium catalysed coupling reactions.

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Communication | Special issue | Vol 28, No. 1, 1989, pp. 167 - 170
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DOI: 10.3987/COM-88-S74
A New Stereoselective Synthesis of (—)-Periplanone-B

Shigefumi Kuwahara and Kenji Mori*

*Faculty of Agricultural and Life Sciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan


Optically pure (-)-periplanone-B, a sex pheromone component of the American cockroach (Periplaneta americana), was synthesized from (S)-3-cyclohexene-1-carboxylic acid in 18 steps. About 300 mg of the crystalline pheromone was obtained in 11% overall yield.

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Communication | Special issue | Vol 28, No. 1, 1989, pp. 171 - 174
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DOI: 10.3987/COM-88-S77
Xanthates as a Source of Stabilised Carbon Centered Radicals Using Visible Light

François Mestre, Catherine Tailham, and Samir Z. Zard*

*Laboratoire de Syntèse, Ecole Polytechnique, 91128 Palaiseau, France


Stabilised alkyl radicals can be generated and trapped in useful yields by irradiating the corresponding S-alkyl xanthates with visible light in the presence of catalytic amounts of 0-ethyl S-benzoyl xanthate.

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Communication | Special issue | Vol 28, No. 1, 1989, pp. 175 - 182
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DOI: 10.3987/COM-88-S90
Intermolecular Trapping by Indole of a Spiroindolenine Intermediated Formed during the Bischler-Napieralski Cyclisation of N-Acetyltryptamine

Jonathan R. Frost,* Bernard R. P. Gaudillière, Elisabeth Kauffmann, Denis Loyaux, Nadine Normand, Geneviève Petry, Philippe Poirier, Ernest Wenkert, and Alexander E. Wick

*Laboratories d‘Etudes et de Recherches Synthélabo, Dept. of Chemistry, 31, avenue Paul Vaillant Couturier, 92220 Bagneux, France


The Bischler-Napieralski cyclisation of N-aoetyltryptamine (1a) in the presence of indole (15) affords a moderate yield of the diastereomeric spiroindolines 9 and 10 suggesting the intermediacy of a spiroindolenine 2a in this reaction. Evidence is provided to show that the minor reaction products 2-methyltryptamine (11), tris-(3-indolyl)methane (12) and 6-[(o-aminophenyl) methyl]-5,11-dihydroindolo[3,2-b]carbazole (13) are derived from the spiroindolines 9 and 10.

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Communication | Special issue | Vol 28, No. 1, 1989, pp. 183 - 186
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DOI: 10.3987/COM-88-S94
Hydrogen Transfer Reduction of Isoflavones

K. Wähälä and T. A. Hase*

*Department of Chemistry, University of Helsinki, Vuorikatu 20, SF-00100 Helsinki, Finland


Hydrogen transfer reduction of isoflavones using ammonium formate and palladium charcoal provides an easy access to polyoxyisoflavanones and also to isoflavan-4-ols without the need for protection of the hydroxy groups. Optimized reaction conditions for improved isoflavanone yields are also discussed.

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Communication | Special issue | Vol 28, No. 1, 1989, pp. 187 - 194
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DOI: 10.3987/COM-88-S100
Absence of Heteroatom Kinetic Effects in π-Route to Carbocations

Alex Nickon,* Stella S. Jones, and Billy J. Parkhill

*Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218, U.S.A.


In solvolyses of prototypical tricyclic and bicyclic heterocycles, suitably positioned oxygen, nitrogen, or sulfur ring-atoms have little net kinetic influence on π routes to carbocations.

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Communication | Special issue | Vol 28, No. 1, 1989, pp. 195 - 202
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DOI: 10.3987/COM-88-S104
Studies on the Total Synthesis of 6-Amido-1-methylcarbapenems

Mark L. Greenlee,* Frank P. DiNinno, and Thomas N. Salzmann

*Merck Sharp and Dohme Research Laboratories, Rahway, NJ 07065, U.S.A.


The synthesis of 6-acylamino- and 6-phthalimido-1-methylcarbapenem derivatives via intramolecular Wittig cyclization is described.

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Communication | Special issue | Vol 28, No. 1, 1989, pp. 203 - 208
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DOI: 10.3987/COM-88-S105
Synthesis and Properties of Unusually Stable, Heterocyclic Nitrilium Ylides

Wolfgang Pfleiderer*

*Fakultät für Chemie, Universität Konstanz, Posttach 5560, D-7750 Konstantz, Germany


7-Azido-1,3-disubstituted lumazines show at elevated temperatures two new ring contractions leading to 9-cyanoxanthines and a new type of stable purin-8-yl nitrilium ylides. This high stability is due to a strong resonance stabilization of the negatively charged purinyl anion moiety, which does not even afford a bulky substituent at the nitrilium C-atom to counteract secondary reactions. The structures of the new nitrilium ylides have been proven by spectral means and comparisons with model substances.

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Communication | Special issue | Vol 28, No. 1, 1989, pp. 209 - 212
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DOI: 10.3987/COM-88-S106
A Convenient Stereoselective Synthesis of α-Glycosyl Esters

Anthony G. M. Barrett* and Barend C. B. Bezuidenhoudt

*Department of Chemistry, Northwestern University, Evanston, Illinois 60208, U.S.A.


The anomeric hydroxyl group of 2,3,4,6-tetra-0-bemyl-D-glucopyranose was esterified by reaction of the derived anomeric alkoxide with 2-acylthio-3-nitropyridines at -78°C. The resultant esters were obtained with high anomerie diastereoselectivity (α:β - 6.5:1 - 22:1). The method wan extended to 2,3,4,6-tetra-0-methyl-D-glucopyranose (α:β 11:1) and 2,3,4,6-tetra-0-benzyl-D-mannopyranose (α only).

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 213 - 217
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DOI: 10.3987/COM-88-S6
Isoltion and Structure of Rollinisation 2: A New Cell Growth Inhibitory Acetogenin from Rollinia mucosa

George R. Pettit,* Roland Riesen, John E. Leet, Judith Polonsky, Cecil R. Smith, Jean M. Schmidt, Claude Dufresne, Daniel Schaufelberger, and Chiristion Moretti

*Center Research Institute, Department of Chemisty, Arizona State University, Main Campus, P.O. Box 872404, Tempe, AZ 85287-2404, U.S.A.


A new cell growth inhibitory acetogenin, designated rolliniastatin 2, has ken isolated from seeds of the South American Rollinia mucosa (Annonaccae) and its structure determined. A diastereomeric relationship for rolliniastatin 1, rolliniasratin 2, and asimicin was proposed.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 219 - 238
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DOI: 10.3987/COM-88-S3
Synthesis of Some Novel 16-Azaestorones and 17-Aza-D-homoestorones. The X-Ray Crystal Structure of 3-Methoxy-16-aza-14β-1,3,5-(10)-estratrien-15-one

Thomas G. Back,* Kurt Brunner, Penelope W. Codding, and Alksander W. Roszak

*Department of Chemistry, University of Calgary, Calgary, Alberta, T2N 1N4, Canada


The efficient syntheses of several new 16-azaestrones and 17-aza-D-homoestrones from estrone methyl ether are reported. These include 3-methoxy-17-aza-D-homo-1,3,5(10)-estratrien-17a-one (2). 3-methoxy-17-aza-D-homo-1,3,5(10)-estratrien-16-one (3) and the 14α and 14β epimers of 3-methoxy-16-aza-1,3,5(10)-estratrien-15-one (4 and 5, respectively). Novel carbinol amide derivatives 27a,27b and 28 of the 16-azaestrone system were also prepared. The configuration at C-14 of azaestrones 4 and 5 was suggested on the basis of thermodynamic arguments, supported by evidence derived from 1H-nmr spectra, and confirmed by an X-ray crystal structure of the 14β-isomer.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 239 - 248
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DOI: 10.3987/COM-88-S4
Synthesis and Rearrangements of Imidazolo- and Triazolo-Diazines

H. S. El Khadem,* J. Kawai, and D. L. Swartz

*Department of Chemistry, The American University, 4400 Massachusetts Avenue, N.W., Washington, D.C. 20016-8014, U.S.A.


3-Methylimidazolo [1,5-a]pyridine and 3-methyl-1,2,4-triazolo[4,3-a]-pyrazine were propared by coupling ethyl dithioacetate with 2-(aminomethyl)-pyridine and 2-hydrazinopyrazine, respectively. Both compoonds are stable in dilute acids and bases, unlike 3-methyl-1,2,4-triazolo[4,3-a]pyrimidine obtained by coopling the same dithioacetate with 2-hydrazinopyrimidine, which quickly undergose a Dimroth type rearrangement. Coupling ethyl dithioacetate with 2-hydrazino-4-hydroxy-6-methylpyrimidine yielded a mixture of 3,5-dimethyl-1,2,4-triazolo[4,3-a]-7(8H)-pyrimidone and 3,7-dimethyl-1,2,4-triazolo[4,3-a]-5(8H)-pyrimidone, which were identified by 2D nmr. The last compound underwent a Dimroth rearrangement with acids to yield 2,5-dimethyl-1,2,4-triazolo[1,5-a]-7(4H)-pyrimidone, whereas the first did not. Finally, coupling ethyl dithioacetate with 5-chloro-4-hydrazinopyrimidine afforded 8-chloro-3-methyl-1,2,4-triazolo[4,3-c]pyrimidine, which upon treatment with acids underwent a reversible ring opening to afford 2-chloro-1-formamido-2-(5-methyl-1,3,4-triazolo-2-yl)ethene. The latter on pyrolysis gave the starting base without undergoing rearrangement.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 249 - 258
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DOI: 10.3987/COM-88-S5
Oxygenation of the Unactivated Pyridine System by Acetyl Hypofluorite Made Directly from F2

Shlomo Rozen* and David Hebel

*School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv university, Tel Aviv, 69978, Israel


Acetyl hypofluorite was found capable of activating the usually unreactive pyridine by substituting the hydrogen at the 2 position by an acetoxy group which then was hydrolyzed to the corresponding pyridinone. Substituents at 3, 4 or 5 position do not interfere with the reaction, but compounds with substituents at 2 (with the exception of aromatic ones) either do not react or produce tars. The reaction conditions are very mild and the yields are very good for this kind of substitution. Quinolines and pyrazines also react very satisfactorily.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 259 - 268
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DOI: 10.3987/COM-88-S9
1,3-Dipolar Cycloadditions of Diazoalkanes to Heteroaromatic System. The Synthesis of Triazolo[4,3-b][1,2]diazepine and Cyclopropa[e]pyrazolo[4,3-c]azolo[1,5-a]pyridine Derivatives

Branko Stanovnik, Gorazd Habjan, Miha Tisler, Ljubo Golic, and Ivan Leban

*Department of Chemistry, E. Kardelj University, Murnikova 6, 61000 Ljubljana, Slovenia


1,3-Dipolar cycloaddition of 2-diazopropane to 6-methyl-8-phenylsulphonyl-s-triazolo[4,3-b]pyridazien (4), 6-nitro-s-triazolo[4,3-a]pyridine (9) and 6-nitrotetrazolo[1,5-a]pyridine (10) produced the corresponding cycloadducts, which were transformed into derivatives of s-triazolo [4,3-b] [1,2]diazepine (5), cyclopropa [e] pyrazolo[4,3-c]-s-triazolo [1,5-a] pyridine (13) and cyclopropa [e] pyrazolo [4,5-c] tetrazolo [1,5-a] pyridine (14), respectively.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 269 - 273
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DOI: 10.3987/COM-88-S11
Synthesis of 2-Oxazolidineselones

Anders kjær* amd Troels Skrydstrup

*Department of Organic Chemistry, The Techinacaol University of Denmark, 2800 Lyngby, Denmark


A series of 2-oxazolidineselones are synthesized by mercuric chloride assisted reactions of 1,2-aminoalcohols and carbon diselenide.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 275 - 282
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DOI: 10.3987/COM-88-S12
The Alternative Synthesis of Isoquinoline Nucleus Using the Thermal Electrocyclic Reaction of 1-Azahexa-1,3,5-triene System

Satoshi Hibino,* Eiichi Sugino, Yukiko Adachi, Kazuhiko Nomi, Kohichi Sato, and Keiichiro Fukumoto

*Graduate School of Pharmacy and Pharmaceutical Sciences, Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Fukuyama, Hiroshima 729-0292, Japan


The thermal electrocyclic reaction of 2-alkenylbenzaldoximes or their derivatives having conjugated 1-azahexatriene system in o-dichlorobenzene gave isoquinolines in moderate to good yields except the reaction of unsubstituted 2-alkenylbenzaldoxime and its oxime ethers.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 283 - 294
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DOI: 10.3987/COM-88-S13
Chiral Synthesis via Organoboranes. 19. The Successful One-Carbon Homologation of Heterocyclic Boronate Esters with High Optical Purity

Herbert C. Brown,* Ashok K. Gupta, Milind V. Rangaishenvi, and J. V. N. Vara Prasad

*H. C. Brown and R. B. Wetherill Laboratories of Chemistry, Purdue University, West Lafayette, Indiana 47907-1393, U.S.A.


An exploratory study was undertaken to establish the applicability of the one carbon homologation to heterocyclic boronic esters. This procedure involves the use of (cholomethyl)lithium, LiCH2Cl, generated in situ by the reaction of bromochoromethane and n-BuLi in THF at-78°C in the presence of an enantiomerically pure heterocyclic boronic ester. These heterocyclic boronic esters were prepared via asymmetric hydoroboration of representative heterocyclic olefins bearing either an endocyclic or exocyclic double bond with either Ipe2BH or IpeBH2 in THF.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 295 - 301
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DOI: 10.3987/COM-88-S22
The Asymmetric Total Synthesis of (+)-Reticuline

A. I. Meyers* and Joseph Guiles

*Department of Chemistry, Colorado State University, Fort Collins, CO 80523-1872, U.S.A.


The synthesis of the title compound was accomplished via chiral formamidines in 5 steps (30.4% overall) and 98.6% ee.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 303 - 313
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DOI: 10.3987/COM-88-S26
Synthesis of Vinca Alkaloids and Related Compounds. XLIII. Unexpected Rearrangement of 3-Acylindolenines

Zsuzsanna Kardos-Balogh, Ferenc Sóti, Mária Incze, Mária Kajtár-Peredy, Lajos Radics, and Csaba Szántay*

*Department of Chemistry, Chungnam National University, Yusung, Daejon 305-764, Korea


The stable 3-acylindolenine derivative (1) was transformed to new heterocyclic compounds (7,9) through unusual rearrangements.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 315 - 320
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DOI: 10.3987/COM-88-S31
The Aberrant Biosynthesis of Bromoglaucines

Dewan S. Bhakuni,* Sudah Jain, and Meenakshi Singh

*Central Institute of Medicinal and Aromatic Plants, Lucknow 226016, India


The incorporation of racemic 5-bromoreticuline (8) and 2’,5-dibromoreticuline (9) into 3-bromoglaucine (2) and 3,8-dibromoglaucine (2) respectively in Litsea glutinosa (Lour.) C.B. Roxb. glabraria var. glabraria Hook. (Menispermaceae) has been studied and specific incorporation of 8 and 9 into 2 and 3 was respectively demonstrated. Further, it was demonstrated that the plants do not metabolize 8 and 9 to form glaucine (1).

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 321 - 331
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DOI: 10.3987/COM-88-S37
A [3+2] Cycloaddition Strategy to the Phyllanthocin Ring System

Barry M. Trost and Kevin D. Moeller

*Department of Chemistry, School of Pharmacy, University of Wisconsin, 425 North Charter Street, Madison, Wisconsin 53706, U.S.A.


A general approach to methyleneoxabicyclo[n.3.0]alkyl heterocycles involves the intramolecular palladium catalyzed addition of trimethylsilylmethylallyl cazboxylates to carbonyl groups. Such reactions require tin mediators and 0,N-bis(trimethylsilyl)acetamide to prevent protodesilylation. Both 4-methylene-2-oxabicyclo[3.3.0]octane and 7-methylene-9-oxabicyclo[4.3.0]nonan have been produced Whereas, the former is produced as a single diastereomer, the latter is produced as a mixture whose composition depends upon the presence of substituents. The core ring system of phyllanthocin has been produced in this way.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 333 - 346
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DOI: 10.3987/COM-88-S32
From Steroids to Macrolides

Annette Prelle and Ekkehard Winterfeldt*

*Institut fur Organische Chemie, Universität Hannover, Schneiderberg 1 B, D-30167 Hannover, Germany


Ansa-seco steroids of type 2 - easily obtained from ring B 5,7-butadienes - are shown to undergo stereoselctive epoxidation reactions and regioselective Baeyer-Villiger oxidations to form 15-membered lactones.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 347 - 358
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DOI: 10.3987/COM-88-S17
Phosphorus-nitrogen Componds. Part 58. The Reactions of Hexachlorocyclotriphosphazatriene with Ethane-, 1,3-Propane- and 1,4-Butane-Diols. Spiro, Ansa, Bridged and Dangling Derivatives and Their 31P and 1H Nuclear Magnetic Resonance Spectra

Abdulla H. Alkubaisi, Harold G. Parkes, and Robert A. Shaw

*Department of Chemistry, Birkbeck College, University of London, Malet Street, London WC1E 7HX, U.K.


The reactions of hexachlorocyclotriphosphazatriene with ethane-,1,3-propane- and 1,4-butanediole give the following derivatives: (i) spiro N3P3[0(CH2)n0]xCl6-2x, (x=1,2 and 3; n = 2,3 and 4), ansa N3P3[0(CH2)0]Cl4, spiro-ansa N3P3[0(CH2)30]2Cl2, bridged N3P3Cl5[0(CH2)n0]N3P3Cl5(n = 3 and 4) and dangling N3P3[0(CH2)nOH]Cl5 (n = 3 and 4). The 31P and 1H nmr spectra of the above compounds were investigated.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 359 - 363
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DOI: 10.3987/COM-88-S34
Two Step Redox System LII: 2,2’-Bipyridylboronium Salts

Siegfried Hünig* and Ingeborg Wehner

*Institut für Organische Chemie, Universität Wurzburg, Am Hubland, D-97074 Wurzburg, Germany


Dications 1 derived from 2,2-bipyridine are found to exist as fully reversible two step redox systems with persistent radical ions (SEM) of high thermodynamic stability, if the bridge X forces the two pyridine rings into coplanar positions. The well known derivative 1a (DiquatR) is now complemented by the boronium ions 1c and 1e-1g, as shown by voltammetry and the uv spectra of the corresponding radicals.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 365 - 372
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DOI: 10.3987/COM-88-S43
Phenolic Congeners of Colchicine: Preparation and Characterization of Phenolic and Catecholic Analogues of Colchicine, Colchiceine and Thiocolhicine

Anjum Muzaffar, Maria Chrzanowska, and Arnold Brossi*

*Section of Medical Chemistry, Laboratory of Analytical Chemistry, NIDDK, National Institute of Health, Bethesda, MD 20982, U.S.A.


Trearment of 2-demethylcolchicine (2) with sulfuric acid afforded 1,2-didemethylcolchicine (6) as the major, and 2,3-didemethylcolchieine (8) as the minor product. 2,3-Didemethylcolchicine (8) was prepared from 3-ethoxycarbonyl-3-demethylcolchicine by sulfuric acid treatment. Hydrolysis of catecholie compounds 6 and 8 with 0.1 N hydrochloric acid afforded colehiceines 13 and 14, respectively. Ester derivatives of 2-demethyl- and 3-demethylcolehicine, and of catechols 6 and 8 were prepared. A direct conversion of 2 into 3-demethylthiocolchicine (15) and conversion of 15 into ester derivatives is described. Cleavage of the ether groups of colchicine by boron tribromide is also reported.

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Paper | Special issue | Vol 28, No. 1, 1989, pp. 373 - 381
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DOI: 10.3987/COM-88-S47
The Reactions of Allyl o-Bromoaryl Ethers, N-Allyl o-Bromoacetanilide, and Related Compounds with Tributyltin Hydride in the Presence of Activated Olefins

Hideo Togo and Osamu Kikuchi

*Department of Chemistry, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba-shi, Ibaraki, 305-8571, Japan


o-Bromophenyl allyl ether, N-ally1 o-bromoacetanilide, and related compounds reacted with tributyltin hydride in the presence of activated olefins to give 2,3-dihydrobenzofuran, 2,3-dihydroindole, and analogous derivatives in modest yields respectively via both intra- and intermolecular radical C-C bond formations.

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