Synthesis of indolocarbazoles via annulations of chromium carbene complexes

Merlic, Craig A.; McInnes, Daniel M.; You, Ying

doi:10.1016/s0040-4039(97)01595-5

Cited by 32 publications

(33 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A variety of natural products that show anti-tumour activity as well as protein kinase C inhibitory properties contain an indolecarbazole motif in their structure. In their 1997 studies Merlic and his group 79,80 prepared the unsymmetrical 2,2′-biindole 59, as substrates for a pivotal benzannulation reaction, via the Suzuki coupling of the boronic ester 58 and 2-iodoindole (Scheme 16). The authors studied the effects of a range of different nitrogen protecting groups upon the subsequent coupling reaction.…”

Section: Scheme 15mentioning

confidence: 99%

The Synthesis and Applications of Heterocyclic Boronic Acids

Tyrrell¹,

Brookes²

2003

Synthesis

166

121

View full text Add to dashboard Cite

Boronic acids are valued by organic chemists for their important role in the synthesis of biphenyls via a palladium(0) catalysed cross-coupling reaction with aryl halides (Suzuki reaction). Despite their synthetic utility and known biological activities heterocyclic boronic acids feature less frequently often due to difficulties in their synthesis. This paper provides an overview of the synthesis and applications of a range of heterocyclic boronic acids. 5Conclusions

show abstract

Section: Scheme 15mentioning

confidence: 99%

The Synthesis and Applications of Heterocyclic Boronic Acids

Tyrrell¹,

Brookes²

2003

Synthesis

166

121

View full text Add to dashboard Cite

show abstract

“…Table 14 Photo-driven Benzannulation Reactions This photodriven benzannulation was used in the synthesis of indolocarbazoles (Eq. 22) [96] and calphostins (Eq. 23) [97].…”

Section: S Hegedusmentioning

confidence: 99%

Photoinduced Reactions of Metal Carbenes in Organic Synthesis

Hegedus

2004

Metal Carbenes in Organic Synthesis

View full text Add to dashboard Cite

The photoinduced reactions of metal carbene complexes, particularly Group 6 Fischer carbenes, are comprehensively presented in this chapter with a complete listing of published examples. A majority of these processes involve CO insertion to produce species that have ketene-like reactivity. Cycloaddition reactions presented include reaction with imines to form b-lactams, with alkenes to form cyclobutanones, with aldehydes to form b-lactones, and with azoarenes to form diazetidinones. Photoinduced benzannulation processes are included. Reactions involving nucleophilic attack to form esters, amino acids, peptides, allenes, acylated arenes, and aza-Cope rearrangement products are detailed. A number of photoinduced reactions of carbenes do not involve CO insertion. These include reactions with sulfur ylides and sulfilimines, cyclopropanation, 1,3-dipolar cycloadditions, and acyl migrations.

show abstract

“…Thus, when the dienyl carbene arising from the reaction of 1 a with the sterically hindered nitrone, N ‐(1‐methylethylidene)‐1‐methylethylamine‐ N ‐oxide ( 4 d ) was treated with tert ‐butylisocyanide in THF, only a 45 % yield of the corresponding aniline derivative 7 i was isolated (Table 2, entry 11). On the other hand, trimethylsilylcyanide, which is known to react through its isomeric form with Fischer dienyl carbenes,6 did not allow us to efficiently prepare the desired benzisoxazole derivatives. Although small amounts of the final product were detected in the 1 H NMR spectrum of the crude mixture, the major product of the reaction of 5 a with trimethylsilylcyanide was the amide derived from the hydrolysis of the ketenimine intermediate (see Experimental Section).…”

Section: Resultsmentioning

confidence: 99%

“…It is noteworthy that the double bond involved in the cyclization belongs to an aromatic ring in most cases reported to date. This reaction has been successfully applied to the preparation of analogues of indolocarbazole natural products6 and to the total synthesis of calphostins 7…”

Section: Introductionmentioning

confidence: 99%

Efficient Synthesis of Highly Functionalized Indazoles and 2,3-Dihydro-1,2-benzisoxazoles by Reaction of Stable Fischer Dienyl Carbenes and Isocyanides

2001

View full text Add to dashboard Cite

A range of stable chromium and tungsten Fischer dienyl carbenes have been prepared by [3+2] cycloaddition of alkenylethynyl carbene complexes with nitrones or diazoalkanes. Treatment of these systems with isocyanides gives entry to highly functionalized 2,3-dihydro-1,2-benzisoxazoles and indazoles in a completely regioselective fashion, under mild conditions, and with high yields. This methodology can be also applied to the preparation of analogous naphthoisoxazoles starting from arylethynyl Fischer complexes. Reductive cleavage of the isoxazole moiety in the prepared heterocycles also enables the efficient synthesis of highly substituted p-aminophenols.

show abstract

Synthesis of indolocarbazoles via annulations of chromium carbene complexes

Cited by 32 publications

References 19 publications

The Synthesis and Applications of Heterocyclic Boronic Acids

The Synthesis and Applications of Heterocyclic Boronic Acids

Photoinduced Reactions of Metal Carbenes in Organic Synthesis

Efficient Synthesis of Highly Functionalized Indazoles and 2,3-Dihydro-1,2-benzisoxazoles by Reaction of Stable Fischer Dienyl Carbenes and Isocyanides

Contact Info

Product

Resources

About