Evolving Digital Circuits Using Complex Building Blocks

Author(s):  
Paul Bremner ◽  
Mohammad Samie ◽  
Gabriel Dragffy ◽  
Tony Pipe ◽  
James Alfred Walker ◽  
...  
Synthesis ◽  
2021 ◽  
Author(s):  
John F. Bower ◽  
Timothy P. Aldhous ◽  
Raymond W. M. Chung ◽  
Andrew G. Dalling

AbstractStrategies that enable the efficient assembly of complex building blocks from feedstock chemicals are of paramount importance to synthetic chemistry. Building upon the pioneering work of Murai and co-workers in 1993, C–H-activation-based enantioselective hydroarylations of alkenes offer a particularly promising framework for the step- and atom-economical installation of benzylic stereocenters. This short review presents recent intermolecular enantioselective Murai-type alkene hydroarylation methodologies and the mechanisms by which they proceed.1 Introduction2 Enantioselective Hydroarylation Reactions of Strained Bicyclic Alkenes3 Enantioselective Hydroarylation Reactions of Electron-Rich Acyclic Alkenes4 Enantioselective Hydroarylation Reactions of Electron-Poor Acyclic Alkenes5 Enantioselective Hydroarylation Reactions of Minimally Polarized Acyclic Alkenes6 Conclusion and Outlook


2009 ◽  
Vol 74 (5) ◽  
pp. 651-769 ◽  
Author(s):  
Alain Braun ◽  
Il Hwan Cho ◽  
Stephane Ciblat ◽  
Dean Clyne ◽  
Pat Forgione ◽  
...  

Enantioselective approaches to the construction of four complex building blocks of the structurally intricate marine macrolide known as spongistatin 1 are presented. The first phase of the synthetic effort relies on a practical approach to a desymmetrized, enantiomerically pure spiroketal ring system incorporating rings A and B. Concurrently, the C17–C28 subunit, which houses one-fifth of the stereogenic centers of the target in the form of rings C and D, was assembled via a composite of stereocontrolled aldol condensations. Once arrival at the entire C1–C28 sector had been realized, routes were devised to provide two additional highly functionalized sectors consisting of C29–C44 and C38–C51. A series of subsequent transformations including cyclization of the E ring and hydroboration to afford the B-alkyl intermediate for the key Suzuki coupling to append the side chain took advantage of efficient stereocontrol. Ultimately, complete assembly and functionalization of the western EF sector of spongistatin was thwarted by an inoperative Suzuki coupling step intended to join the side chain to the C29–C44 sector, and later because of complications due to protecting groups, which precluded the complete elaboration of the late stage C29–C51 intermediate.


2010 ◽  
Vol 63 (8) ◽  
pp. 1159 ◽  
Author(s):  
Jun Ma ◽  
Jeremy W. Bartels ◽  
Zhou Li ◽  
Ke Zhang ◽  
Chong Cheng ◽  
...  

With an ever increasing interest in the combined functionality and versatility of materials, increasing demands are placed on synthetic methodologies by which to produce such materials. This work demonstrates the preparation of block copolymers having fluorocarbon content, pyrrolidinone units, and alkene groups as complex building blocks for the assembly of discrete nanoparticles in solution and, alternatively, transformation into sophisticated crosslinked networks. Reversible addition–fragmentation chain transfer (RAFT) polymerization is a facile tool for the synthesis of well-defined polymers containing imbedded side-chain functionalities. In this work, the synthesis of well-defined multifunctional fluorinated polymers bearing pendant pyrrolidinone groups, and block copolymers bearing both pyrrolidinone and alkenyl groups on different segments was achieved, by using RAFT polymerizations of unique bifunctional monomers. Upon micellization, the amphiphilic diblock copolymers were transformed into regioselectively-functionalized nanoparticles. Further transformations of pyrrolidinone- and alkene-dual functionalized-block copolymers into complex amphiphilic networks were accomplished by highly efficient UV-induced thiol-ene reactions. Whether as discrete nanoparticles or nanoscopically-segregated crosslinked networks, these materials have great potential for several diverse technologies, including as anti-fouling materials.


2020 ◽  
Author(s):  
Hui Li ◽  
Fengqian Chen ◽  
Xinyu Guan ◽  
JIali Li ◽  
Cuiyan Li ◽  
...  

<a>The growth of three-dimensional covalent organic frameworks (3D COFs) with new topologies is still considered as a great challenge due to limited availability of high-connectivity building units. Here we report the design and synthesis of novel 3D triptycene-based COFs, </a><a></a><a>termed</a> JUC-568 and JUC-569, following the deliberate symmetry-guided design principle. By combining a triangular prism (6-connected) node with a planar triangle (3-connected) or another triangular prism node, the targeted COFs adopt unreported <b>ceq </b>or non-interpenetrated <b>acs</b> topology, respectively. <a>Both materials</a> show permanent porosity and impressive performance <a>in the adsorption of CO<sub>2</sub></a> (~ 98 cm<sup>3</sup>/g at 273 K and 1 bar), CH<sub>4</sub> (~ 48 cm<sup>3</sup>/g at 273 K and 1 bar), and especially H<sub>2</sub> (up to 274 cm<sup>3</sup>/g or 2.45 wt% at 77 K and 1 bar), which is <a>highest </a>among <a>porous organic materials</a> reported to date. This research thus provides a promising strategy for diversifying 3D COFs based on complex building blocks and promotes their <a></a><a>potential applications</a> <a>in</a><a></a><a> energy storage and environment-related field</a>s.


2013 ◽  
Vol 13 (8) ◽  
pp. 3773-3784 ◽  
Author(s):  
Višnja Vrdoljak ◽  
Biserka Prugovečki ◽  
Dubravka Matković-Čalogović ◽  
Tomica Hrenar ◽  
Renata Dreos ◽  
...  

2019 ◽  
Vol 16 (1) ◽  
pp. 70-97 ◽  
Author(s):  
Xiaohua Cai ◽  
Mengzhi Yang ◽  
Hui Guo

Background: Enamines and their variant enamides as powerful and versatile synthons have attracted great attention in synthetic chemistry. Enamides display unique stability and reduce enaminic reactivity in view of the electron-withdrawing effect of N-acyl group. A great deal of satisfactory achievements in the synthesis and application of enamides has been made in recent years. Especially, tertiary enamides without N-H bond regarded as low reactivity of compounds in the past can act as excellent nucleophiles to react with electrophiles for the construction of various nitrous molecules. </P><P> Objective: This review focuses on recent advances on tertiary enamides in the synthetic strategies and applications including addition, coupling reaction, functionalization and electro- or photo-chemical reaction. Conclusion: Tertiary enamides as electron-deficient nucleophiles display a satisfactory balance between stability and reactivity to offer multiple opportunities for the construction of various functionalized nitrogencontaining compounds. Further exploration of the reactive mechanisms involved tertiary enamides and the development of novel and efficient transformations to generate ever more complex building blocks starting from tertiary enamides are particularly worth pursuing.


IUCrJ ◽  
2018 ◽  
Vol 5 (1) ◽  
pp. 13-21 ◽  
Author(s):  
Marijana Đaković ◽  
Željka Soldin ◽  
Boris-Marko Kukovec ◽  
Ivan Kodrin ◽  
Christer B. Aakeröy ◽  
...  

In order to develop transferable and practical avenues for the assembly of coordination complexes into architectures with specific dimensionality, a strategy utilizing ligands capable of simultaneous metal coordination and self-complementary hydrogen bonding is presented. The three ligands used, 2(1H)-pyrazinone, 4(3H)-pyrimidinone and 4(3H)-quinazolinone, consistently deliver the required synthetic vectors in a series of CdII coordination polymers, allowing for reproducible supramolecular synthesis that is insensitive to the different steric and geometric demands from potentially disruptive counterions. In all nine crystallographically characterized compounds presented here, directional intermolecular N—H...O hydrogen bonds between ligands on adjacent complex building blocks drive the assembly and orientation of discrete building blocks into largely predictable topologies. Furthermore, whether the solids are prepared from solution or through liquid-assisted grinding, the structural outcome is the same, thus emphasizing the robustness of the synthetic protocol. The details of the molecular recognition events that take place in this series of compounds have been clearly delineated and rationalized in the context of calculated molecular electrostatic potential surfaces.


2020 ◽  
Author(s):  
Hui Li ◽  
Fengqian Chen ◽  
Xinyu Guan ◽  
JIali Li ◽  
Cuiyan Li ◽  
...  

<a>The growth of three-dimensional covalent organic frameworks (3D COFs) with new topologies is still considered as a great challenge due to limited availability of high-connectivity building units. Here we report the design and synthesis of novel 3D triptycene-based COFs, </a><a></a><a>termed</a> JUC-568 and JUC-569, following the deliberate symmetry-guided design principle. By combining a triangular prism (6-connected) node with a planar triangle (3-connected) or another triangular prism node, the targeted COFs adopt unreported <b>ceq </b>or non-interpenetrated <b>acs</b> topology, respectively. <a>Both materials</a> show permanent porosity and impressive performance <a>in the adsorption of CO<sub>2</sub></a> (~ 98 cm<sup>3</sup>/g at 273 K and 1 bar), CH<sub>4</sub> (~ 48 cm<sup>3</sup>/g at 273 K and 1 bar), and especially H<sub>2</sub> (up to 274 cm<sup>3</sup>/g or 2.45 wt% at 77 K and 1 bar), which is <a>highest </a>among <a>porous organic materials</a> reported to date. This research thus provides a promising strategy for diversifying 3D COFs based on complex building blocks and promotes their <a></a><a>potential applications</a> <a>in</a><a></a><a> energy storage and environment-related field</a>s.


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