Intramolecular aza-Wittig Reaction Research Articles

Facile Synthesis of 1,4-Benzodiazepin-5-one Derivatives via Intramolecular Aza-Wittig Reaction. Application to an Efficient Synthesis of O-Benzyl DC-81

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTFacile Synthesis of 1,4-Benzodiazepin-5-one Derivatives via Intramolecular Aza-Wittig Reaction. Application to an Efficient Synthesis of O-Benzyl DC-81Shoji Eguchi, Keizo Yamashita, Yuji Matsushita, and Akikazu KakehiCite this: J. Org. Chem. 1995, 60, 13, 4006–4012Publication Date (Print):June 1, 1995Publication History Published online1 May 2002Published inissue 1 June 1995https://doi.org/10.1021/jo00118a016RIGHTS & PERMISSIONSArticle Views727Altmetric-Citations46LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (990 KB) Get e-Alerts Get e-Alerts

Synthesis of pyrrolo[2,1- c][1,4]benzodiazepines via an Intramolecular Aza-Wittig reaction. Synthesis of the antibiotic DC-81

A new and efficient synthesis of the pyrrolo[2,1- c][1,4]benzodiazepine ring system has been carried out using, as a key step, an intramolecular aza Wittig reaction of the appropriately substituted N-(2-azidobenzoyl)pyrrolidine-2-carboxaldehydes. The parent unsubstituted PBD 4 and the natural product DC-81 have been prepared in the imine form in good overall yields.

On the reactions of (vinylimino)phosphoranes and related compounds. Part 30. Short new synthesis of 5-azaazulene derivatives. Some comments on reactivities of (vinylimino)phosphoranes

A short new synthesis of phenyl-substituted and annulated 5-azaazulene (cyclopenta[c]azepine) derivatives 15–18 consists of the reaction of [(1-phenylvinyl)imino]- and benz-annulated [(cycloalkenyl)imino]-phosphoranes 8–11 with 5-(dimethylaminomethylene)cyclopenta-1,3-dienecarbaldehyde 1 in an enamine alkylation (Michael addition) process, subsequent proton migration–ketonization, and condensation of the formyl group with the iminophosphorane moiety (aza-Wittig reaction). On the other hand, reactions of aldehyde 1 with (vinylimino)phosphoranes12–14, which have no phenyl group at the α-position relative to the nitrogen atom, consist of a intramolecular aza-Wittig reaction or a substitution reaction of aldehyde 1 with phosphoranes 12–14 and subsequent hydrolysis to afford 5-(aminomethylene)cyclopenta-1,3-dienecarbaldehyde 19 and its derivatives 20 and 21, respectively. In the context of selectivity observed in the reaction of phosphoranes 8–11 and 12–14 with aldehyde 1, respectively, MNDO calculations on compounds 1 and 12A, 12B as well as on model compounds 8C–12C were performed to gain insight via a theoretical interpretation based upon frontier molecular orbital theory (FMO): the former reaction, giving 5-azaazulene derivatives, would be an FMO-controlIed reaction, while the latter is a charge-controlled reaction. Several spectral and chemical properties of heterocycles of 16–18 are analysed.

A concise enantiospecific synthesis of nuphar piperidine alkaloids: total synthesis of (–)-anhydronupharamine, (–)-nupharamine, (–)-nuphenine and (+)-3-epinupharamine

Enantiospecific syntheses of (–)-anhydronupharamine, (–)-nupharamine, (–)-nuphenine, and (+)-3-epinupharamine are achieved starting from (–)-or (+)-carvone as chiral sources, in which a regioselective reductive fragmentation of the cyclopentane derivatives and an intramolecular aza–Wittig reaction were involved as key reactions.

Iminophosphoranes: Useful Building Blocks for the Preparation of Nitrogen-Containing Heterocycles

The almost centenarian reaction of iminophosphoranes with carbonyl or heterocumulene compounds (aza-Wittig reaction) is presented in this review, but with focus mainly on publications of the last decade. Both inter- and intramolecular versions of the aza-Wittig reaction are discussed, including for the latter mono and tandem cyclizations. The feasibility of preparing several kinds of nitrogen-containing heterocycles by this method has been systematically examined. Several successful examples of the synthesis of natural products, using the iminophosphorane-mediated cyclization as the key step, have demonstrated the maturity of the field and its excellent prospects. 1. Introduction 2. Intermolecular Aza-Wittig Reaction 3. Intramolecular Aza-Wittig Reaction 3.1. Ketones 3.2. Esters 3.3. Acyl Chlorides 3.4. Amides 3.5. Carboxylic Acid Anhydrides 4. Reaction of Iminophosphoranes with Alcohols and Oxiranes 5. Tandem Reactions 5.1.Tandem Aza-Wittig/Electrocyclic Ring Closure 5.1.1.Pyrido Annulation 5.1.1.1. Synthesis of c-Fused Pyridines 5.1.1.2. Synthesis of b-Fused Pyridines 5.1.2. Pyrimido Annulation 5.2. Tandem Aza-Wittig/Heterocumulene-Mediated Annulation 6. Consecutive Processes 7. Cyclization of Phosphazides

Ａｚａ‐Ｗｉｔｔｉｇ反応による含窒素複素環合成法の最近の進歩

Recent advances in synthetic method of heterocyclic compounds by aza-Wittig reaction, i.e., the imination using iminophosphoranes, are here reviewed. Examples are systematically presented depending on the direct cyclization route by intramolecular aza-Wittig reaction, or the sequential route via intermolecular aza-Wittig reaction, followed by various types of cyclizations such as electrocyclic reaction, Diels-Alder cycloaddition, and nucleophilic heterocyclization etc. The feasibility of this method in synthesis of nitrogen-heterocycles is emphasized in this review.

Synthesis of 2,3,6,7-tetrahydro- and 2,3,4,5,6,7-hexahydro-1H-1,4-diazepines via a tandem Michael-type addition–intramolecular aza-Wittig sequence

Intramolecular aza-Wittig reaction of azides derived from 1, 2-amino azides and α, β-unsaturated ketones leads to 2, 3, 6, 7-tetrahydro-1H-1, 4-diazepines. Reduction of these compounds with lithium aluminium hydride atfords the corresponding saturated heterocycles.

Short-step Synthesis of Rutecarpine and Tryptanthrin via Intramoleculer Aza-wittig Reaction

A convenient short-step synthesis of rutecarpine and tryptanthrin as quinazoline alkaloids containing indole skeleton via intramolecular aza-Wittig reaction was described

A new route to 1,3-benzoxazepines and 1,3-benzodiazepines via intramolecular aza-Wittig reaction

The reaction of triphenylphosphine with the o-acyloxy-5 and o-acylamino-azidocinnamates 9, prepared from salicylaldehyde and o-aminobenzaldehyde, results in ring closure to give the 1,3-benzoxazepines 7 and 1,3-benzodiazepines 12,via the intramolecular aza-Wittig reaction of the iminophosphoranes 6 and 10 initially formed, respectively.

NOVEL HETEROCYCLIC COMPOUNDS VIA AZA- AND BIS-AZA-WITTIG REACTIONS

Abstract Two quinoxaline derivatives, 1 and 2, were prepared via a bis-aza-Wittig reaction when the suitable aromatic diamine was treated with (MeO)3PBr2/Et3N followed by the addition of benzil. Also, two additional novel heterocyclic compounds, 4 and 6 were prepared via an intramolecular aza-Wittig reaction.

Novel ring enlargement of lactams via quinazolinone annelation. A facile route to benzoannelated large-membered cyclic 1,5-diamines

A novel route to benzoannelated large-membered cyclic 1,5-diamines from lactams is described. Thus, n-membered lactams 1 were N-acylated by o-azidobenzoyl chloride 5 to afford the corresponding imides 4. These were treated with tributylphosphine and underwent an intramolecular aza-Wittig reaction to give n-membered ring-fused quinazolinones 2 in 84-96% yield. By reductive cleavage of 2 with BH 3 •THF, (n+4)-membered cyclic diamines 3 were obtained in 52-95% yield

Darstellung 2‐methoxysubstituierter Pyrrole durch intramolekulare Aza‐Wittig‐Reaktionen

Preparation of 2‐Methoxy‐Substituted Pyrroles by Aza‐Wittig Reactionsα‐Halo ketones and dimethyl malonate can be transformed by Knoevenagel condensation and nucleophilic displacement of halogen with sodium azide into the azide esters 10. These azides undergo ring closure to 2‐methoxy‐substituted pyrroles 11 by intramolecular Aza‐Wittig reaction.

A New Synthetic Route to 1,3-Benzoxazepines

A novel method for the synthesis of 5-hydroxy-1,3-benzoxazepines 5 utilizing the Staudinger reaction followed by an intramolecular aza-Wittig reaction, from o-acyloxyphenacyl azides 2 is reported.

Heterocycles by intramolecular aza-Wittig reactions of iminophosphoranes obtained from 2-azidobenzoyl- and 2-azidobenzylidene derivatives

Iminophosphoranes have been used in intramolecular aza-Wittig reactions to prepare pyrrolo[1,2-a]benzimidazoles, fused quinazolinones, quinolines, and an isoindolo[1,3,4]benzotriazepinone.

ChemInform Abstract: The Reactivity of Imide Carbonyl Groups in the Intramolecular Aza‐Wittig Reaction. An Efficient Route to Iminolactam Derivatives.

Treatment of N-(ω-azidoalkyl)imides with triphenylphosphine in toluene or xylene under reflux gave the corresponding iminolactam derivatives in good yields via the Staudinger reaction followed by the intramolecular aza-Wittig reaction.

A new efficient synthesis of imidazolinones and quinazolinone by intramolecular aza-Wittig reaction

A new synthesis of imidazolinones and quinazolinones by intramolecular aza-Wittig reaction is described. Readily available azido substituted imides 4 , 6 , 10 , and 12 reacted with triphenylphosphine or tributylphosphine to afford the corresponding imidazolinones 1 , 7 and quinazolinones 2 , 12 via the Staudinger reaction, followed by an intramolecular aza-Wittig reaction.

The reactivity of imide carbonyl groups in the intramolecular aza-Wittig reaction. An efficient route to iminolactam derivatives

Treatment of N-(ω-azidoalkyl)imides with triphenylphosphine in toluene or xylene under reflux gave the corresponding iminolactam derivatives in good yields via the Staudinger reaction followed by the intramolecular aza-Wittig reaction.

Synthesis of novel carbo- and heteropolycycles. 12. A new versatile synthesis of oxazoles by intramolecular aza-Wittig reaction

Synthesis of novel carbo- and heteropolycycles. 12. A new versatile synthesis of oxazoles by intramolecular aza-Wittig reaction

A new route to quinazolinones via intramolecular aza-Wittig reaction

Treatment of the imide derivatives 1 and 3 readily obtainable from 2-azidobenzoyl chloride and the corresponding amide derivatives with triphenylphosphine or tributylphosphine in xylene at room temperature gave quinazolinones 2 and 4 in excellent yields via the Staudinger reaction, followed by the intramolecular aza-Wittig reaction.

ChemInform Abstract: Synthesis of Novel Azaheteropolycycles via Bridgehead Imines and Bridge Imines

Recent advances in the synthesis of some novel azamodified polycyclic systems have been reviewed emphasizing the synthetic utility of bridgehead imines as well as bridge imines, which have been easily obtained by azide functionalizations of appropriate bi-and tricarbocycles, followed by photolysis, acidolysis, and/or intramolecular aza-Wittig reactions.