Directed remote Metalation synthesis

Snieckus and Fu reported a new general and regiospecific synthesis of 9-phenanthrols involving direct ortho-metalation, Suzuki cross-coupling, and an LDA-mediated directed remote metalation sequence (Eq. (11)) [27]. 

James, C.A. (1998) The directed remote metalation - Carbamoyl migration reaction. Total syntheses of the defucogilvocarcins and amottin 1 and synthesis of heteroarylfused benzopy-ranones. Ph.D. Thesis. University of Waterloo, Canada. 

Directed remote Metalation (DreM). Anionic Counterpoints to Classical Processes for Condensed Aromatic and Heteroaromatic Synthesis... 

Directed ortho Metalation (DoM). The synthesis of the alkaloid schumarmiophytine requires a silicon protection of the more reactive ortho 0-carbamate site to set the stage for the key step, a remote anionic Fries rearrangement that results in a pyridine ring carbamoyl translocation (eq 48). ... 

Wang, W. (1991) Directed ortho and remote aromatic metalation synthesis of highly substituted biaryls, dibenzo(b,d)pyranones and 3,3 -substituted-l,l -bi-2-naphthols. M.Sc. Thesis. University of Waterloo, Canada. 

The modern tools available in synthetic chemistry, either from the organic viewpoint or concerning the preparation of transition metal complexes, allow one to prepare more and more sophisticated molecular systems. In parallel, time-resolved photochemistry and photophysics are nowadays particularly efficient to disentangle complex photochemical processes taking place on multicomponent molecules. In the present chapter, we have shown that the combination of the two types of expertise, namely synthesis and photochemistry, permits to tackle ambitious problems related to artificial photosynthesis or controlled dynamic systems. Although the two families of compounds made and studied lead to completely different properties and, potentially, to applications in very remote directions, the structural analogy of the complexes used is striking. 

Stoichiometric use of transition-metal-carbene complexes in organic synthesis has been thoroughly reviewed.Various examples using carbene complexes containing cyclopropane subunits have been reported.Here, the cyclopropyl moiety is either attached directly to the carbene carbon or is placed in a more remote position. This section only discusses isolated carbene complexes. Related transition-metal-catalyzed conversions of diazo compounds containing cyclopropane subunits, which are interpreted to proceed via carbene intermediates (e.g. ref 130), are not discussed here. 

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