Despite the inherent sustainability direct arylation polymerization (DArP) offers through a C−H activation pathway, the use of expensive homogeneous Pd catalysts remains problematic for large-scale conjugated polymer (CP) synthesis. Herein, the first report on the recycling of heterogeneous catalysts for CP synthesis using DArP is presented. We found SiliaCat Pd-DPP to be a highly efficient and recyclable catalyst for multi-batch CP synthesis providing CPs with molecular weights (M n ) up to 82 kg/ mol even after being recycled three times. Batch-to-batch variations were further optimized to afford up to five batches of polymers with a M n of 25 ± 2.5 kg/mol without structural disparity. Significantly, this work discloses among the most sustainable CP synthesis protocols to date and presents the critical concept of catalyst-recycling to the important field of organic semiconducting polymers, which potentially enables access to truly low-cost flow chemistry for industrial-scale CP synthesis.
To address the issue of generating large amounts of organic waste from conjugated polymer synthesis, the first direct arylation polymerization (DArP) protocol under emulsion conditions is disclosed with a 10-fold reduction of organic solvent utilized.
<p>Biomimetic total synthesis has played a pivotal role in the development of synthetic organic chemistry. In particular, efforts aimed at mimicking the head-to-tail (HT) cation–π cyclization cascades invoked in terpene biosynthesis, such as those catalyzed by type-II cyclases, have led to a multitude of new synthetic methods, chemical concepts, and total syntheses over the past century. Conversely, synthetic methodology that mimics tail-to-head (TH) cation–π cyclization cascades, mediated by Mg<sup>2+</sup> type-I terpene cyclases, remains elusive in organic synthesis, despite key roles in the biosynthesis of privileged therapeutic molecules such as taxol and artemesinin. Here we report that Li<sup>+</sup>/weakly-coordinating anion (WCA) salts catalyze the TH polycyclization of linaloyl fluoride, leading to high-yielding mixtures of polycyclic terpene natural products including cedrenes, cadinadiene, epizonarene, and 𝛿-selinene. The examples reported herein are the first small molecule-catalyzed TH polycyclization reactions enabling the shortest (formal) total synthesis of (<i>±</i>)-artemisinin. Moreover we apply this strategy to the diterpene geranyllinaloyl fluoride, resulting in a two-step total synthesis of the tricyclic core of the gersemiols (named here as <i>α</i>-gersemiene), a recently discovered class of marine diterpenoid natural products.</p>
<p>Biomimetic total synthesis has played a pivotal role in the development of synthetic organic chemistry. In particular, efforts aimed at mimicking the head-to-tail (HT) cation–π cyclization cascades invoked in terpene biosynthesis, such as those catalyzed by type-II cyclases, have led to a multitude of new synthetic methods, chemical concepts, and total syntheses over the past century. Conversely, synthetic methodology that mimics tail-to-head (TH) cation–π cyclization cascades, mediated by Mg<sup>2+</sup> type-I terpene cyclases, remains elusive in organic synthesis, despite key roles in the biosynthesis of privileged therapeutic molecules such as taxol and artemesinin. Here we report that Li<sup>+</sup>/weakly-coordinating anion (WCA) salts catalyze the TH polycyclization of linaloyl fluoride, leading to high-yielding mixtures of polycyclic terpene natural products including cedrenes, cadinadiene, epizonarene, and 𝛿-selinene. The examples reported herein are the first small molecule-catalyzed TH polycyclization reactions enabling the shortest (formal) total synthesis of (<i>±</i>)-artemisinin. Moreover we apply this strategy to the diterpene geranyllinaloyl fluoride, resulting in a two-step total synthesis of the tricyclic core of the gersemiols (named here as <i>α</i>-gersemiene), a recently discovered class of marine diterpenoid natural products.</p>
<p>Biomimetic total synthesis has played a pivotal role in the development of synthetic organic chemistry. In particular, efforts aimed at mimicking the head-to-tail (HT) cation–π cyclization cascades invoked in terpene biosynthesis, such as those catalyzed by type-II cyclases, have led to a multitude of new synthetic methods, chemical concepts, and total syntheses over the past century. Conversely, synthetic methodology that mimics tail-to-head (TH) cation–π cyclization cascades, mediated by Mg<sup>2+</sup> type-I terpene cyclases, remains elusive in organic synthesis, despite key roles in the biosynthesis of privileged therapeutic molecules such as taxol and artemesinin. Here we report that Li<sup>+</sup>/weakly-coordinating anion (WCA) salts catalyze the TH polycyclization of linaloyl fluoride, leading to high-yielding mixtures of polycyclic terpene natural products including cedrenes, cadinadiene, epizonarene, and 𝛿-selinene. The examples reported herein are the first small molecule-catalyzed TH polycyclization reactions enabling the shortest (formal) total synthesis of (<i>±</i>)-artemisinin. Moreover we apply this strategy to the diterpene geranyllinaloyl fluoride, resulting in a two-step total synthesis of the tricyclic core of the gersemiols (named here as <i>α</i>-gersemiene), a recently discovered class of marine diterpenoid natural products.</p>
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.