Relationships between the carbon-oxygen stretching frequencies of carboxylato complexes and the type of carboxylate coordination

In studying the evolution of organic chemistry and grasping its essence, one comes quickly to the conclusion that no other type of reaction plays as large a role in shaping this domain of science than carbon-carbon bond-forming reactions. The Grignard, Diels-Alder, and Wittig reactions are but three prominent examples of such processes, and are among those which have undeniably exercised decisive roles in the last century in the emergence of chemical synthesis as we know it today. In the last quarter of the 20th century, a new family of carbon-carbon bond-forming reactions based on transition-metal catalysts evolved as powerful tools in synthesis. Among them, the palladium-catalyzed cross-coupling reactions are the most prominent. In this Review, highlights of a number of selected syntheses are discussed. The examples chosen demonstrate the enormous power of these processes in the art of total synthesis and underscore their future potential in chemical synthesis.

Palladium-catalyzed cross-coupling reactions in total synthesis.

Sol-gel chemistry of transition metal oxides

The design and implementation of cascade reactions is a challenging facet of organic chemistry, yet one that can impart striking novelty, elegance, and efficiency to synthetic strategies. The application of cascade reactions to natural products synthesis represents a particularly demanding task, but the results can be both stunning and instructive. This Review highlights selected examples of cascade reactions in total synthesis, with particular emphasis on recent applications therein. The examples discussed herein illustrate the power of these processes in the construction of complex molecules and underscore their future potential in chemical synthesis.

Cascade reactions in total synthesis.

The Diels-Alder reaction has both enabled and shaped the art and science of total synthesis over the last few decades to an extent which, arguably, has yet to be eclipsed by any other transformation in the current synthetic repertoire. With myriad applications of this magnificent pericyclic reaction, often as a crucial element in elegant and programmed cascade sequences facilitating complex molecule construction, the Diels-Alder cycloaddition has afforded numerous and unparalleled solutions to a diverse range of synthetic puzzles provided by nature in the form of natural products. In celebration of the 100th anniversary of Alder's birth, selected examples of the awesome power of the reaction he helped to discover are discussed in this review in the context of total synthesis to illustrate its overall versatility and underscore its vast potential which has yet to be fully realized.

https://www.ch.ic.ac.uk/local/organic/pericyclic/DA.pdf

The Diels--Alder reaction in total synthesis.

Methyleneketenes and methylenecarbenes. xiii. cycloaddition of ketenes and of f a 1-pyrroline 1-oxide to isopropylideneketene

REACTION OF Γ-NITRO KETONES WITH THIONYL CHLORIDE: FORMATION AND X-RAY CRYSTAL STRUCTURE OF AN α-SULFINYL KETONE

Coordination chemistry of methylmercury(ii). synthesis, hydrogen-1 nmr, and crystallographic studies of cationic complexes of mehg(ii) with ambidentate and polydentate ligands containing pyridyl and n-substituted imidazolyl donors and

The title compound crystallizes in space group P21/c with a= 6·429(6), b= 13·619(14), c= 10·047(10)A, β= 107·88(1)°, Z= 2. The structure has been determined by Patterson and Fourier methods and refined to R 0·057 from three-dimensional diffractometer data (1325 observed reflections). Its structure consists of discrete monomeric units which are required crystallographically to be centrosymmetric. The two chlorine atoms are in a trans arrangement and the bond distances Mo–Cl, Mo–O, and Mo–N are respectively 2·39, 1·95, and 2·14 A.

Bryan M. Gatehouse

Papers

Methyleneketenes and methylenecarbenes. xiii. cycloaddition of ketenes and of f a 1-pyrroline 1-oxide to isopropylideneketene

REACTION OF Γ-NITRO KETONES WITH THIONYL CHLORIDE: FORMATION AND X-RAY CRYSTAL STRUCTURE OF AN α-SULFINYL KETONE

Coordination chemistry of methylmercury(ii). synthesis, hydrogen-1 nmr, and crystallographic studies of cationic complexes of mehg(ii) with ambidentate and polydentate ligands containing pyridyl and n-substituted imidazolyl donors and

Crystal and molecular structure of trans-dichlorobis-(n-methylsalicylaldiminato)molybdenum(iv)

Unusual Formation of New Indole-Containing Heterocyclic Ring Systems.