Tetsuo Nozoe's “Autograph Books by Chemists 1953–1994”: An Essay

Note from the Editor: It is with special pleasure and a warm feeling of gratitude that I introduce Koji Nakanishi's essay which accompanies the publication of the fifth segment of the Tetsuo Nozoe Autograph Books. This project, “Bonding beyond Borders,” is a symbol of the ever‐increasing connectivity among the many members of the chemistry community. Both Nakanishi and Nozoe wrote autobiographies in the Profiles, Pathways and Dreams series that I edited from 1985 to 1997. I learned from their books how close they were as friends and as colleagues. My interest in publishing the Nozoe Autograph Books goes back many years but was stymied by the difficulty of finding a publisher. This interest was rekindled when, in 2006, Nakanishi told me about – and eventually lent me – a one volume specially printed commemorative collection of the Nozoe Autograph Books. At an ACS National meeting, I rushed to show this book to Eva Wille who could not put it down. This was the entry, the personal connection, that led to the publication of the Nozoe Autograph Books by Wiley‐VCH in The Chemical Record. This is another example of bonding, of enthusiasm and commitment, within our community. Jeffrey I. Seeman Guest Editor, University of Richmond Richmond, Virginia 23173, USA     

Our Future,Our Heritage. The Chemical Family Tree of Tetsuo Nozoe

Note from the Editor: When I was editing Tetsuo Nozoe's autobiography Seventy Years in Organic Chemistry in the late 1980s, I realized that the history of Japanese organic chemistry was not too well known in countries other than Japan. I urged Professor Nozoe to include the historical context of his life in his writings, and I was absolutely delighted that he did so. I also suggested that he publish a “Riko Majima Family Tree in Chemistry.” Majima was not only Nozoe's professor but, as detailed in Nozoe's autobiography and elsewhere in the literature, the father figure of Japanese organic chemistry. Nozoe was reluctant because to single‐out some chemical academics but not others in such a public manner could—would—prove embarrassing. But faithful to his profession, the obligations to history prevailed and Nozoe's autobiography contains the Majima Family Tree. We now skip ahead 25 years where we are immersed in the publication of the Nozoe Autograph Books (see: http://www.tcr.wiley‐vch.de/nozoe and this introductory essay: J. I. Seeman, Chem. Rec. 2012 , 12, 517–531). I find myself once again an editor studying in the life and legacies of Riko Majima and Tetsuo Nozoe. The “repeating experiences” of history have been felt once again! ² I asked Professors Ichiro Murata, Shô Itô, and Toyonobu Asao (who are Professor Nozoe's students and biographers) to follow Professor Nozoe's lead and provide his Family Tree in Chemistry. What follows is a reproduction of the Majima Family Tree as provided by Professor Nozoe along with the next generation Family Tree, that being the students of Tetsuo Nozoe's students who themselves became illustrious professors. —Jeffrey I. Seeman Guest Editor University of Richmond Richmond, Virginia 23173, USA E‐mail: jseeman@richmond.edu     

The Nozoe Autograph Books: Why Sign Them? Why Publish Them? Why Read Them? Why Treasure Them? Personal and Professional Reflections

Note from the Editor: The Nozoe Autograph Books project involves the publication of the entire 1179 pages of Tetsuo Nozoe's autograph books in 15 consecutive issues of The Chemical Record. In the design of this project, three of us—Eva Wille, Brian Johnson and I—had a vision of bringing a wide range of experiences to our communities of readers. We also had an eye to the archival future. The final design included, with each of these issues of The Chemical Record, an essay that would provide context, novel content and especially enjoyable reading, to round out the project. In the 10 issues published to date, and in the others that will follow, the essays range from personal stories to perspectives in the areas of chemistry near and dear to the heart of Tetsuo Nozoe. Eva Wille's essay is particularly special. The daughter of a professor of chemistry of Nozoe's generation at the Ludwig‐Maximilians‐Universität München (Franz Wille, 1909—1986), Wille is a Ph.D. chemist herself, and for many years, has been and is a major figure in the world of scientific publishing. Thus, she has a unique perspective to share. Indeed, all of the authors of these essays have shared their very personal and professional perspectives, and we are thankful for all of them—and for Tetsuo Nozoe and the thousands of our friends and colleagues who signed his books. —Jeffrey I. Seeman Guest Editor University of Richmond Richmond, Virginia 23173, USA E‐mail: jseeman@richmond.edu     

Extraordinary Transformations to Achieve the Synthesis of Remarkable Aromatic Compounds

Note from the Editor: When we walk around a sculpture, it can speak to us in many ways, sometimes quite differently from various view points. Central to Tetsuo Nozoe and the Nozoe Autograph Book project are novel aromatic compounds. Just look at nearly any page and such compounds jump out at us. We can categorize them in many ways. Their structures. Their physical properties. Their pharmacological and toxicological properties. Their commercial utilities. Their symmetry. Their size. In this essay, Graham Bodwell brings to us his analysis of the various ways in which some of the most remarkable of these compounds have been ingeniously synthesized. We are privileged to have Bodwell's vision and his sense of organization and beauty. Tetsuo Nozoe would have beamed! —Jeffrey I. Seeman Guest Editor University of Richmond Richmond, Virginia 23173, USA E‐mail: jseeman@richmond.edu     

Facets of the Tetsuo Nozoe Legacy Immortalized in an Enduring Series of International Symposia on Novel Aromatic Compounds (ISNA)

Note from the Editor: According to Robert K. Merton (1988), “Invisible college” is a term used “to designate the informal collectives of scientists interacting in their research on similar problems, these groups being generally limited to a size ‘that can be handled by interpersonal relationships.’ ” Invisible colleges can be highly competitive, even ugly in their priority races, or they can be congenial, even enthusiastically supportive to its members. In the community of organic chemists who studied novel aromatic chemistry in the 1950s–1990s, one man—Tetsuo Nozoe—is largely responsible for bringing together researchers from across the world and setting the tone of brotherhood. Larry Scott, today a senior scholar of that invisible college, warmly shares the spirit of Tetsuo Nozoe with each of us in the following essay. Jeffrey I. Seeman Guest Editor University of Richmond Richmond, Virginia 23173, USA E‐mail: jseeman@richmond.edu     

Domino Reactions Based on Combinatorial Bond Transformations in Electron‐Deficient Tertiary Enamines

Electron‐deficient enamines such as enaminones and enaminoesters are moieties showing widespread application in organic synthesis. Among the various available electron‐deficient enamines, the N,N‐disubstituted amino‐functionalized ones (tertiary enamines) represent a class of special enamines with distinct properties and important applications. Based on our longstanding interest in exploring novel synthetic methods using electron‐deficient tertiary enamines, we present herein the research advances in organic synthesis via domino reactions making use of the combinatorial C–N, C=C, C–H, and other bond transformations of electron‐deficient tertiary enamines.

     

The Structure‐property Relationships of D‐π‐A BODIPY Dyes for Dye‐sensitized Solar Cells

BODIPY dyes have attracted considerable attention as potential photosensitizers in dye‐sensitized solar cells (DSSCs) owing to their excellent optical properties and facile structural modification. This account focuses on recent advances in the molecular design of D‐π‐A BODIPY dyes for applications in DSSCs. Special attention has been paid to the structure‐property relationships of D‐π‐A BODIPY dyes for DSSCs. The developmental process in the modified position at the BODIPY core with a donor/acceptor is described. The devices based on 2,6‐modified BODIPY dyes exhibit better photovoltaic performance over other modified BODIPY dyes. Meanwhile, the research reveals the correlation of molecular structures (various donor chromophores, extended units, molecular frameworks, and long alkyl groups) with their photophysical and electrochemical properties and relates it to their performance in DSSCs. The structure‐property relationships give valuable information and guidelines for designing new D‐π‐A BODIPY dyes for DSSCs.

     

Applications of Chiral Squaramides: From Asymmetric Organocatalysis to Biologically Active Compounds

This review seeks to provide coverage on the recent advances in chiral squaramide‐catalyzed asymmetric transformations and their applications in the synthesis of a variety of chiral biologically active compounds. It aims to give an overview highlighting the new reaction types and enantioenriched medicinal scaffolds developed in the last few years.

     

Sulfonyl Azoles in the Synthesis of 3‐Functionalized Azole Derivatives

Sulfonyl indoles, as well as related azolyl derivatives, have been recently introduced in synthesis as stable precursors of reactive indolenine intermediates. This personal account reports on the discovery of sulfonyl azoles and their practical utilization in many synthetic processes for the preparation of functionalized 3‐substituted indoles, indazoles, and pyrroles. The indolenine intermediates obtained by treatment of sulfonyl azoles with Brønsted bases or Lewis acids can be considered as vinylogous imino derivatives that can be made to react with different nucleophilic reagents. These include organometallic reagents, reducing agents, stabilized carbanions, and heteronucleophiles. The controlled and mild conditions for the generation of indolenines from sulfonyl azoles make these substrates particularly useful in asymmetric synthesis, exploiting organo‐ or metal‐catalyzed processes. Although less exploited, sulfonyl indoles can also be involved in photochemical processes for the preparation of polycyclic derivatives.

     

Organo‐ and Organometallic‐Catalytic Intramolecular [1,5]‐Hydride Transfer/Cyclization Process through C(sp3)–H Bond Activation

The direct functionalization of C(sp³)–H bonds is one of the most synthetically powerful research areas in current organic synthesis. Organocatalytic C(sp³)–H bond activation reactions have recently been developed in addition to the traditional metal‐catalyzed C(sp³)–H activation reactions. In this review, we aim to give a brief overview of organo‐ and organometallic internal redox cascade reactions with respect to the mechanism, the reactivity of hydrogen donors and acceptors, and the migration modes of hydrogen.

     

Development of C3‐Symmetric Tris‐Urea Low‐Molecular‐Weight Gelators

This article describes recent developments in C₃‐symmetric tris‐urea low‐molecular‐weight gelators and their applications. The C₃‐symmetric tris‐ureas are excellent frameworks to form supramolecular polymers through noncovalent interactions. In organic solvents, hydrophobic tris‐ureas form supramolecular gels. Amphiphilic tris‐ureas form supramolecular gels in aqueous media. Functional supramolecular gels were prepared by introducing appropriate functional groups into the outer sphere of tris‐ureas. Supramolecular hydrogels obtained from amphiphilic tris‐ureas were used in the electrophoresis of proteins. These electrophoreses results showed several unique characteristics compared to typical electrophoreses results obtained using polyacrylamide matrices.

     

Aminoglycoside Antibiotics: New Insights into the Biosynthetic Machinery of Old Drugs

2‐Deoxystreptamine (2DOS) is the unique chemically stable aminocyclitol scaffold of clinically important aminoglycoside antibiotics such as neomycin, kanamycin, and gentamicin, which are produced by Actinomycetes. The 2DOS core can be decorated with various deoxyaminosugars to make structurally diverse pseudo‐oligosaccharides. After the discovery of biosynthetic gene clusters for 2DOS‐containing aminoglycoside antibiotics, the function of each biosynthetic enzyme has been extensively elucidated. The common biosynthetic intermediates 2DOS, paromamine and ribostamycin are constructed by conserved enzymes encoded in the gene clusters. The biosynthetic intermediates are then converted to characteristic architectures by unique enzymes encoded in each biosynthetic gene cluster. In this Personal Account, we summarize both common biosynthetic pathways and the pathways used for structural diversification.

     

Bio‐/Chemosensors and Imaging with Aggregation‐Induced Emission Luminogens

Aggregation‐induced emission (AIE) luminogens show abnormal fluorescent behavior; they are non‐emissive in solution, but they become strongly emissive after aggregation. Sensing and imaging are the major applications of AIE luminogens. By properly manipulating the aggregation and deaggregation of AIE molecules, various bio‐/chemosensors have been developed. Moreover, AIE molecules with targeting groups have been devised for imaging of organelles and cancer cells. In this account, we report our recent work on the application of AIE luminogens for the construction of bio‐/chemosensors and imaging.

     

Radical‐Mediated Fluoroalkylations

Recently, the development of eco‐friendly radical processes has become of great interest in synthetic chemistry. In particular, visible‐light photocatalysis has drawn tremendous attention for its environmental compatibility and versatility in promoting many synthetically important reactions. In addition, inorganic electrides as electron donors have emerged as new eco‐friendly tools for radical transformations since they consist of non‐toxic and naturally abundant main metals such as calcium. The design of new fluoroalkylation reactions has benefited greatly from recent advances in visible‐light photocatalysis and the chemistry of inorganic electrides. Since adding fluoroalkyl groups can dramatically change the physical and chemical properties of organic compounds, using these processes to promote eco‐friendly radical fluoroalkylations will have a major impact in areas such as pharmaceuticals, agrochemicals, and material sciences. This Personal Account reviews radical‐mediated fluoroalkylations, such as trifluoromethylations and difluoroalkylations, recently developed in our laboratory.

     

Synthesis of Multisubstituted Olefins through Regio‐ and Stereoselective Addition of Interelement Compounds Having B–Si,B–B,and Cl–S Bonds to Alkynes,and Subsequent Cross‐Couplings

Multisubstituted olefins are fundamental motifs in organic compounds. In this account, we describe the synthesis of organic molecules bearing an olefinic moiety by the transition‐metal‐catalyzed regio‐ and stereoselective addition of a variety of interelement compounds to alkynes. Regio‐ and stereoselective silaboration, diborylation, and chlorothiolation have been achieved by using the transition‐metal catalysts. The subsequent cross‐coupling reactions of the boron‐containing alkenes to install various aryl groups afforded the corresponding tri‐ and tetraarylated olefins. This account describes our research on the highly regio‐ and stereoselective synthesis of multifunctionalized olefins such as tetraarylethenes with four different aryl groups.

     

Extending the Substrate Scope for the Asymmetric Iridium‐Catalyzed Hydrogenation of Minimally Functionalized Olefins by Using Biaryl Phosphite‐Based Modular Ligand Libraries

Asymmetric hydrogenation is one of the most efficient and atom‐economical tools to prepare chiral molecules. However, the enantiodiscrimination of simple, minimally functionalized olefins is still challenging and requires more sophisticated ligand design. Herein, we discuss our progress in the successful development of ligand design for the iridium‐catalyzed asymmetric hydrogenation of minimally functionalized olefins.

     

Ligand Functionalization in Metal–Organic Frameworks for Enhanced Carbon Dioxide Adsorption

Ligand functionalization in metal–organic frameworks (MOFs) has been studied extensively and has been demonstrated to enhance gas adsorption and induce interesting gas adsorption phenomena. This account summarizes our recent study of three series of MOFs by ligand functionalization, as well as their carbon dioxide adsorption properties. While ligand functionalization does not change the overall structure of the frameworks, it can influence their gas adsorption behavior. In the first two series, we show how ligand functionalization influences the CO₂ affinity and adsorption capacity of MOFs. We also show a special case in which subtle changes in ligand functionality alter the CO₂ adsorption profile.

     

Inducing Planar Orientation in Side‐Chain Liquid‐Crystalline Polymer Systems via Interfacial Control

For efficient photoresponses of liquid‐crystal (LC) azobenzene (Az) polymer systems, planar LC orientation of the Az mesogenic group is required because the light irradiation process usually occurs with normal incidence to the film surface. However, LC molecules with a rodlike shape tend to orient perpendicularly to the film surface according to the excluded volume effect theory. This review introduces new approaches for inducing planar orientation in side‐chain LC Az polymer films via interface and surface molecular designs. The planar orientation offers efficient in‐plane photoalignment and photoswitching to hierarchical LC architectures from molecular LC mesogens and LC phases to mesoscopic microphase‐separated structures. These approaches are expected to provide new concepts and possibilities in new LC polymer devices.

     

Recent Developments in the Chiral Brønsted Acid‐catalyzed Allylboration Reaction with Polyfunctionalized Substrates

Asymmetric allylboration has played a central role in organic synthesis ever since the pioneering work by Hoffman and Brown, having found applications in the total synthesis of many natural products. A new dawn for this 40 year‐old reaction occurred with the beginning of the new century when the first catalytic asymmetric methods came into play. In less than one decade, several methodologies, able to achieve the desired homoallylic alcohols with ee ranges in the high 90s, were developed. Among them, in the present account, we will disclose our contribution to the development of the chiral binolphosphoric‐derived Brønsted acid‐catalyzed allylboration of aldehydes originally reported by Antilla in 2010. Our contribution to this field lies in its application to polyfunctionalized systems, both on the aldehyde and the allylboronate in question, which enables the rapid construction of molecular diversity and complexity. Parts of the work described herein have been carried out in collaboration with the groups of Profs. Akiyama and Houk.

     

Wenbin Lin

My favorite subject at school was Chemistry. I chose chemistry as a career because I love the fact we can “Just Do It” without over‐thinking. This and more about Wenbin Lin can be found on page 4472.