8.4.5. Nitromercuration Reactions 3878 9. Hydroamination of Alkenes and Alkynes under Microwave Irradiation 3878 * To whom correspondence should be addressed. Phone: +49 241 8

Hydroamination: direct addition of amines to alkenes and alkynes.

In this critical review we summarize the latest results obtained during the last decade concerning the catalytic activities of organoactinide complexes. We begin with a brief summary of the synthesis and characterization of uranium and thorium complexes that later will be used as catalysts for demanding chemical transformations. Hydroamination, hydrosilylation of terminal alkynes, coupling of terminal alkynes with isonitriles, catalytic reduction of azides and hydrazines, ring opening polymerization of cyclic esters and polymerization of α-olefins are covered in this review (118 references). The topics covered in this review regarding organoactinide chemistry will be of interest to inorganic, organic and organometallic chemists, material and catalytic scientists due to its unique mode of activation as compared to late transition-metals. In addition, the field of organoactinide complexes in catalysis is steadily growing, because of the complementary reactivity of organoactinides as compared to other early or late transition complexes, in demanding chemical transformations.

Recent advances in organothorium and organouranium catalysis.

Iron-Catalyzed Direct Synthesis of Imines from Amines or Alcohols and Amines via Aerobic Oxidative Reactions under Air

There is continuing interest in the development of improved methods for the synthesis of indoles owing to their importance as one of the most represented building block in natural bioactive products and marketed drugs. Thus, indole and its derivatives have been termed “privileged pharmacological structures” as they bind to many biological receptors with high affinity. In recent years, domino sequences in particular have provided efficient complementary access to various indoles. Such sequences start in general from easily available substrates. A reactive intermediate is generated with the aid of a catalyst, which is subsequently transformed to the desired indole. For example, the domino hydroformylation–Fischer indole sequence has evolved into a direct method for the onepot construction of complex indoles from olefins. More recently, Ackermann and Born reported the use of a combination of TiCl4 and tBuNH2 as catalyst for the domino hydroamination–Fischer indole cyclization. In 1991, Bergman et al. reported the first zirconium-mediated synthesis of indoles by trapping a hydrazidozirconocene complex with alkynes and subsequent addition of hydrochloric acid. Then, Odom and co-workers described the first titanium-catalyzed intermolecular hydroamination of arylhydrazines with alkynes. The arylhydrazones obtained have been used further in the Fischer indole reaction to provide N-alkyl and N-aryl indoles in high yield. Based on this elegant approach, we have developed the titanium-catalyzed synthesis of functionalized tryptamines and tryptamine homologues, and tryptophol and tryptophol derivatives, starting from commercially available arylhydrazines and alkynes. A problem which prevents widespread use of this reaction is the sensitivity of the titanium complexes towards functional groups, and the necessity for hydrazine protection and indole deprotection steps. Our continuing interest in indole syntheses led us to look for alternative catalysts for the intermolecular hydrohydrazination. Herein we report the intermolecular zinc-mediated and -catalyzed hydroamination reactions of alkynes which provide a general synthesis of indoles. Our initial investigations involved studying the effect of different metal complexes on themodel reaction ofN-methylN-phenylhydrazine 1a with 1-octyne 2a (Table 1). The

Zinc-promoted hydrohydrazination of terminal alkynes: an efficient domino synthesis of indoles.

Transition metal-catalyzed addition of C-, N- and O-nucleophiles to unactivated C–C multiple bonds

Amidate ligands have been used as a modular ligand set for early transition-metal complexes, and have been found to exhibit high reactivity in the catalytic hydroamination of alkynes, allenes, and alkenes. This microreview focuses on coordination metal complexes containing amidate functionality including their bonding, structure and reactivity trends. The synthesis and characterization of a number of different group-4 metal complexes is presented, and their applications in both hydroamination and organic synthesis are discussed.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

Modular N,O‐Chelating Ligands: Group‐4 Amidate Complexes for Catalytic Hydroamination

Group 4 Bis(pyrimidinoxide) Complexes. Investigations of Electronic Effects in Catalytic Hydroamination

Objectives To evaluate the psychometric properties of HEARTSMAP, an emergency psychosocial assessment and management tool, and its impact on patient care and flow measures. Methods We conducted the study in two phases: first validating the tool using extracted information from a retrospective cohort, then evaluating implementation on a prospective cohort of youth presenting with mental health complaints to a tertiary Pediatric Emergency Department (PED). In phase 1, six PED clinicians applied HEARTSMAP to extracted narratives and we calculated inter-rater agreement for referral recommendations using Cohen’s Kappa and the sensitivity and specificity for identifying youth requiring psychiatric consultation and hospitalization. In phase 2, PED clinicians prospectively used HEARTSMAP and we assessed the impact of the tool’s implementation on patient-related outcomes and Emergency department (ED) flow measures. Results We found substantial agreement (κ=0.7) for cases requiring emergent psychiatric consultation and moderate agreement for cases requiring community urgent and non-urgent follow-up (κ=0.4 each). The sensitivity was 76% (95%CI: 63%, 90%) and specificity was 65% (95%CI: 55%, 71%) using retrospective cases. During pilot implementation, 62 patients received HEARTSMAP assessments: 46 (74%) of HEARTSMAP assessments triggered a recommendation for ED psychiatry assessment, 39 (63%) were evaluated by psychiatry and 13 (21%) were admitted. At follow-up, all patients with HEARTSMAP’s triggered recommendations had accessed community resources. For those hospitalized for further psychiatric care at their index or return visit within 30 days, 100% were initially identified by HEARTSMAP at the index visit as requiring ED psychiatric consultation. Conclusions HEARTSMAP has strong reliability, and when applied prospectively is a safe and effective management tool.

A psychosocial assessment and management tool for children and youth in crisis.

Catalytic hydroamination is combined with the Strecker reaction to yield a one-pot synthesis of α-cyanoamines from terminal alkynes. This methodology is further applied to the synthesis of α-amino acids and α-amino esters.

A Sequential C-N, C-C Bond-Forming Reaction: Direct Synthesis of α-Amino Acids from Terminal Alkynes

The combination of titanium-catalyzed anti-Markovni-kovhydroamination of terminal alkynes with the Strecker reaction isused in the synthesis of unsymmetrical vicinal diamines via the one-potsynthesis of α-cyanoamines. This methodology is further appliedto the efficient synthesis of imidazolidinones. An easy-to-use bis(amidate)titaniumprecatalyst permits efficient approaches to heterocyclic chemistryfrom terminal alkynes.

Alison V. Lee

Papers

Modular N,O‐Chelating Ligands: Group‐4 Amidate Complexes for Catalytic Hydroamination

Group 4 Bis(pyrimidinoxide) Complexes. Investigations of Electronic Effects in Catalytic Hydroamination

A psychosocial assessment and management tool for children and youth in crisis.

A Sequential C-N, C-C Bond-Forming Reaction: Direct Synthesis of α-Amino Acids from Terminal Alkynes

The Direct Synthesis of UnsymmetricalVicinal Diamines from Terminal Alkynes: A Tandem SequentialApproach for the Synthesis of Imidazolidinones