Efficient Synthesis of Imino-methano Tröger Bases by Nitrene Insertions into C–N Bonds

Pujari, Sandip A.; Guénée, Laure; Lacour, Jérôme

doi:10.1021/ol4016892

Cited by 22 publications

(6 citation statements)

References 45 publications

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“…Interestingly, 2 f was formed in quite higher yield (83 %) using PhIO and TMSN 3 in only 1.5 equivalents each. This result is in line with a previously detailed reactivity of 1 f with nitrenes, in which substantial amounts of C−H amination at benzylic positions were noticed over the “classical” aminimide formation . It can be rationalized by the presence of the ortho substituents that shield sterically the nitrogen atoms.…”

Section: Resultssupporting

confidence: 91%

Stereoselective and Enantiospecific Mono‐ and Bis‐C−H Azidation of Tröger Bases: Insight on Bridgehead Iminium Intermediates and Application to Anion‐Binding Catalysis

Bosmani

Pujari

Besnard

et al. 2017

Chemistry A European J

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In the context of Tröger base chemistry, regio- and stereoselective C -H azidation reactions are reported. Azide functional groups are introduced at either one or the two benzylic positions selectively. Mild conditions and good yields are afforded by the combination of TMSN and iodosobenzene PhIO. The process occurs with high enantiospecificity (es 96-99 %) and-interestingly and importantly-via bridgehead iminium intermediates as shown by mechanistic and in-silico studies. Finally, mono- and bistriazole derivatives were prepared in high yields and enantiospecificity by using copper-catalyzed alkyne azide cycloaddition (CuAAC) reactions; some of the products were used as anion-binding organocatalysts for the tritylation of amines and alcohols.

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Section: Resultssupporting

confidence: 91%

Stereoselective and Enantiospecific Mono‐ and Bis‐C−H Azidation of Tröger Bases: Insight on Bridgehead Iminium Intermediates and Application to Anion‐Binding Catalysis

Bosmani

Pujari

Besnard

et al. 2017

Chemistry A European J

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“…In contrast, X–H (X = heteroatom) insertion reactions of metal–nitrenes have remained unexplored . However, on the basis of the analogy between the reactivity of nitrenes and carbenes, we envisioned that the reaction between primary aromatic amines 2 and a Rh II –nitrene should provide N ‐aryl‐ N′ ‐sulfonyldiazenes 1 through N–H insertion of the nitrene followed by oxidation (Scheme ) , …”

Section: Resultsmentioning

confidence: 99%

Rhodium(II)‐Catalyzed Synthesis of N‐Aryl‐N′‐tosyldiazenes from Primary Aromatic Amines Using (Tosylimino)aryliodinane: A Potent Stable Surrogate for Diazonium Salts

et al. 2017

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A single‐step synthesis of N‐aryl‐N′‐tosyldiazenes from primary aromatic amines was developed. A wide range of aromatic amines provided the corresponding products in high yields by N–N bond formation with RhII–nitrene intermediates, which were generated in situ from dirhodium(II) complex catalysts and (tosylimino)‐2,4,6‐trimethylphenyliodinane, followed by oxidation. The synthesized N‐aryl‐N′‐tosyldiazenes were successfully demonstrated to serve as potent and stable surrogates for diazonium salts in the two‐step deaminative transformation of primary aromatic amines.

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“…These ethano‐adducts 1 are essentially unknown. We wondered about their global reactivity and decided to use them as substrates in various reactions, including nitrene insertion reactions 10…”

Section: Methodsmentioning

confidence: 99%

A Mild and Efficient CH₂‐Extrusion Reaction for the Enantiospecific Synthesis of Highly Configurationally Stable Tröger Bases

et al. 2015

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An ovel CH 2 -extrusion reaction leading to the transformation of ethano-Trçger bases into disubstituted methano derivatives is reported (yields up to 93 %). Under mild and metal-free oxidative conditions,aloss of CH 2 and aring contraction are provoked. Despite two bond cleavages at stereogenic nitrogen and carbon centers and at emporary rupture of the bicyclic structure,avery high enantiospecificity (es ! 98 %) is observed for this unusual reaction.Extrusion reactions,w hich are formally the reverse of insertion processes,a re characterized by the removal of an atom or ag roup of atoms from ag iven combination of functional groups and by the reformation of abond between the atoms to which the departing moiety was attached.[1] Such processes are relatively common in organometallic and chalcogen chemistry. [2,3] With more classical organic substrates,only few CH 2 extrusions are reported using metal-free conditions and activated benzylamines and a-hydroxy carbonyl compounds as substrates.[4] Herein, in the context of nitrogen stereochemistry and Tr çger base (TB) derivatives in particular,wereport anovel methylene extrusion which sees the enantiospecific transformation of the ethano-TB 1 into the disubstituted methano-TB 2 (Scheme 1, top). Under mild oxidative conditions,the loss of CH 2 occurs with yields of up to 93 %. Importantly,avery high enantiospecificity (es ! 98 %) is obtained in this reaction which proceeds with retention of configuration through ar ing opening and two bond cleavages at stereogenic nitrogen and carbon centers.Recently,i tw as shown that Tr çger bases of type 3 (Scheme 1, bottom), [5] which are classical chiral molecules as aresult of the presence of stereogenic nitrogen atoms,react in as ingle step with metal carbenes to afford ethano-Trçger bases of type 1.[6] With donor-acceptor diazo reagents as precursors,t he enantiospecificity of the ring expansion is excellent (es 97-99 %

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Efficient Synthesis of Imino-methano Tröger Bases by Nitrene Insertions into C–N Bonds

Cited by 22 publications

References 45 publications

Stereoselective and Enantiospecific Mono‐ and Bis‐C−H Azidation of Tröger Bases: Insight on Bridgehead Iminium Intermediates and Application to Anion‐Binding Catalysis

Stereoselective and Enantiospecific Mono‐ and Bis‐C−H Azidation of Tröger Bases: Insight on Bridgehead Iminium Intermediates and Application to Anion‐Binding Catalysis

Rhodium(II)‐Catalyzed Synthesis of N‐Aryl‐N′‐tosyldiazenes from Primary Aromatic Amines Using (Tosylimino)aryliodinane: A Potent Stable Surrogate for Diazonium Salts

A Mild and Efficient CH₂‐Extrusion Reaction for the Enantiospecific Synthesis of Highly Configurationally Stable Tröger Bases

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Efficient Synthesis of Imino-methano Tröger Bases by Nitrene Insertions into C–N Bonds

Cited by 22 publications

References 45 publications

Stereoselective and Enantiospecific Mono‐ and Bis‐C−H Azidation of Tröger Bases: Insight on Bridgehead Iminium Intermediates and Application to Anion‐Binding Catalysis

Stereoselective and Enantiospecific Mono‐ and Bis‐C−H Azidation of Tröger Bases: Insight on Bridgehead Iminium Intermediates and Application to Anion‐Binding Catalysis

Rhodium(II)‐Catalyzed Synthesis of N‐Aryl‐N′‐tosyldiazenes from Primary Aromatic Amines Using (Tosylimino)aryliodinane: A Potent Stable Surrogate for Diazonium Salts

A Mild and Efficient CH2‐Extrusion Reaction for the Enantiospecific Synthesis of Highly Configurationally Stable Tröger Bases

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A Mild and Efficient CH₂‐Extrusion Reaction for the Enantiospecific Synthesis of Highly Configurationally Stable Tröger Bases