# Upgrading Carbazolyl-Derived Phosphine Ligands Using Rh-I-Catalyzed P-III-Directed C-H Bond Alkylation for Catalytic CO2-Fixation Reactions

Javid Rzayev, Zhuan Zhang, Natacha Durand, Jean-François Soulé

► To cite this version:

Javid Rzayev, Zhuan Zhang, Natacha Durand, Jean-François Soulé. Upgrading Carbazolyl-Derived Phosphine Ligands Using Rh-I-Catalyzed P-III-Directed C-H Bond Alkylation for Catalytic CO2-Fixation Reactions. Organic Letters, 2022, 24 (37), pp.6755-6760. 10.1021/acs.orglett.2c02514. hal-03798100

HAL Id: hal-03798100

https://hal.science/hal-03798100

Submitted on 6 Apr 2023

HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-
entific research documents, whether they are pub-
lished or not. The documents may come from
teaching and research institutions in France or
abroad, or from public or private research centers.

L'archive ouverte pluridisciplinaire HAL, est
destinée au dépôt et à la diffusion de documents
scientifiques de niveau recherche, publiés ou non,
émanant des établissements d'enseignement et de
recherche français ou étrangers, des laboratoires
publics ou privés.

<figure><img src="image_1.png" /></figure>

Distributed under a Creative Commons Attribution 4.0 International License
Upgrading Carbazolyl-Derived Phosphine Ligands using Rh¹-Catalyzed P¹¹I-Directed C–H Bond Alkylation for Catalytic CO₂-Fixation Reactions

Javid Rzayev,ª Zhuan Zhang,ᵇ Natacha Durand,ª and Jean-François Souléª,ᶜ*

a Univ Rennes, CNRS, ISCR UMR 6226, F-35000 Rennes, France

b Present address: Guangxi Key Laboratory of Electrochemical Energy Materials, School of Chemistry and Chemical Engineering, Guangxi University, Nanning, Guangxi 530004, P. R. China

c Present address: Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, 75005 Paris, France

KEYWORDS. Catalysis, ligand design, carbon dioxide, rhodium, and palladium

<figure><img src="image_2.png" /></figure>

**ABSTRACT:** We report a rh(I)-catalyzed C–H bond alkylation of PhenCarPhos [= N-(2-(diphenylphosphaneyl)phenyl)carbazole] and some congener phosphine ligands with alkenes. The C–H bond functionalization occurred exclusively at the C1 position of the carbazolyl unit because the trivalent phosphine acts as a directed group. This protocol provides straightforward access to a large library of C1-alkyl substituted PhenCarPhos, which outperformed common commercial or unfunctionalized phosphines and their precursors in the Pd-catalyzed carbon dioxide-fixation reactions with propargylic amines.

Designing more active ligands is one of the most important fields of catalysis and organometallic chemistry. Despite numerous advances in transition metal-catalyzed reactions, developing efficient catalytic systems is still highly desirable for industrial application, significantly decreasing their environmental impact. Among the different classes of ligands, phosphines remain the most popular with several well-established industrial processes.¹ It is admitted that the associated phosphines can modulate the activity of metal centers of catalysts through fine-tuning of their steric and electronic properties or by weak interactions in the second coordination sphere. However, the synthesis of such multifunctional phosphines with different substituents often requires multistep synthesis and the use of organometallic reagents may limit the diversity of the functional group that can be introduced in the phosphine scaffold.

Since the pioneer observation by Hartwig and co-workers on Pd-catalyzed direct polyarylation of 1-(di-tert-butylphosphino)ferrocene,² P(III)-chelation-assisted C–H bond functionalization has become a straightforward strategy to
quickly generate vast libraries of functionalized phosphines allowing to discover upgraded ligand exhibiting higher catalytic activity in among others Pd catalysis.³ To date, C–H bond functionalizations of phosphines is limited to arylphosphines (borylation,⁴ silylation⁵ and arylation⁶), biarylphosphines (borylation,⁷ silylation, arylation,⁸ alkylation,⁹ alkenylation¹⁰ and carbonylation¹¹) and 1-naphtyphosphines (arylation¹² and alkylation¹³) (Figure 1). Interestingly, in some cases, the C-H bond functionalizations of phosphines give birth to a better ligand in transition-metal catalyzed reactions.¹⁴ For instance, we have demonstrated that C–H bond alkylation of CyJohnPhos (= (2-biphenyl)dicyclohexylphosphine) morphs this inactive ligand into a very active phosphine in Pd-catalyzed carboxylation of aryl bromides with carbon dioxide due to incorporation of amide and ester groups as a basic pendant unit.⁹ª Continuing our efforts to modify phosphines through their C–H bond functionalizations, we turned our attention to PhenCarPhos [= N-(2-(diphenylphosphaneyl)phenyl)carbazole]. Associated with palladium, this ligand, developed by Kwong,¹⁵ exhibits high catalytic activities taking advantage of the introduced carbazolyl unit that i) facilitates the reductive elimination process due to an extended flat-wall-like rigidity and ii) stabilizes active Pd catalytic species during the catalytic cycle through weak interactions with the sp³-hybridized nitrogen atom.

Surprisingly, carbazolyl-derived phosphines have never been subjected to the C–H bond functionalization yet. One reason lies with forming an unconventional 7-membered ring cyclometalated phosphine-metal intermediate. Herein, we report an Rh(I)-catalyzed P(III)-directed C1-alkylation of carbazolyl-derived phosphines with olefins (Figure 1, blue box). This method allows the rapid synthesis of functionalized PhenCarPhos. These modified ligands show promising activity in the Pd-catalyzed CO₂-fixation reaction.

<figure><img src="image_3.png" /><figcaption>**Figure 1.** TM-Catalyzed P(III)-Directed C–H Functionalizations</figcaption></figure>

To explore the C–H bond alkylation of carbazolyl-derived phosphine, we choose PhenCarPhos (1a) and *n*-butyl-acrylate (2a) as the model substrates (Table 1). Based on our previous work on C–H bond alkylation of biarylphosphines,⁹ª we tested firstly the same conditions, namely, [Rh(OAc)(COD)]₂, PivOH in toluene at 140 °C, but no reaction occurred (entry 1). The desired alkylated phosphine 3a was obtained with a conversion of 50% using KOAc instead of PivOH (entry 2). Increasing the amount of KOAc (2 equi.) gave a better conversion (entry 3). Then, we ran the reaction in different solvents (1,4-dioxane, DMF, 1,2-dichloroethane), but none of them outperformed toluene (entries 4-6). NaHCO₃ as a base gives a slightly better result (92% yield, entry 7). Interestingly, commercially available [RhCl(COD)]₂ catalyst displays a similar catalytic activity affording 3a in 87% isolated yield (entry 8). Other Rh(I)-catalysts such as [RhCl(NBE)]₂, [RhCl(COE)]₂, and RhCl(PPh₃)₃ were less efficient, while no reaction occurred with Cp*Rh(III)* catalyst (entries 9-12). Besides, C–H bond alkylation of PhenCarPhos (1) was also achieved using 5 mol% [RuCl₂(*p*-cymene)]₂ catalyst in conjunction with 15 mol%
of AgSbF₆ and 2 equivalents of KOAc (entry 13). However, our attempt to obtain the dialkylation product through increasing the amount of both base and butyl-acrylate or even starting the reaction from **3a** remained unsuccessful (entry 14). Moreover, the phenyl substituents on the phosphorus group are very important, as with two cyclohexyl groups on the phosphorus, no reaction occurred either with rhodium or ruthenium conditions (entries 15 and 16).

<figure><img src="image_4.png" /><figcaption>**Table 1.** Optimization of C–H Alkylation of PhenCarPhos</figcaption></figure>

<table><thead><tr><th>Entry</th><th>Cat</th><th>Additive (y)</th><th>Conv. (%)<sup>a</sup></th><th>3a (%)<sup>a</sup></th></tr></thead><tbody><tr><td>1</td><td>[Rh(OAc)(COD)]<sub>2</sub></td><td>PivOH (1)</td><td>0</td><td>0</td></tr><tr><td>2</td><td>[Rh(OAc)(COD)]<sub>2</sub></td><td>KOAc (0.25)</td><td>50</td><td>45</td></tr><tr><td>3</td><td>[Rh(OAc)(COD)]<sub>2</sub></td><td>KOAc (2)</td><td>89</td><td>82</td></tr><tr><td>4<sup>b</sup></td><td>[Rh(OAc)(COD)]<sub>2</sub></td><td>KOAc (2)</td><td>75</td><td>73</td></tr><tr><td>5<sup>c</sup></td><td>[Rh(OAc)(COD)]<sub>2</sub></td><td>KOAc (2)</td><td>18</td><td>15</td></tr><tr><td>6<sup>d</sup></td><td>[Rh(OAc)(COD)]<sub>2</sub></td><td>KOAc (2)</td><td>0</td><td>0</td></tr><tr><td>7</td><td>[Rh(OAc)(COD)]<sub>2</sub></td><td>NaHCO<sub>3</sub> (2)</td><td>100</td><td>92</td></tr><tr><td>8</td><td>[RhCl(COD)]<sub>2</sub></td><td>NaHCO<sub>3</sub> (2)</td><td>100</td><td>92 (87)</td></tr><tr><td>9</td><td>[RhCl(NBE)]<sub>2</sub></td><td>NaHCO<sub>3</sub> (2)</td><td>85</td><td>81</td></tr><tr><td>10</td><td>[RhCl(COE)]<sub>2</sub></td><td>NaHCO<sub>3</sub> (2)</td><td>84</td><td>79</td></tr><tr><td>11</td><td>RhCl(PPh<sub>3</sub>)</td><td>NaHCO<sub>3</sub> (2)</td><td>10</td><td>8</td></tr><tr><td>12</td><td>[Cp*RhCl<sub>2</sub>]<sub>2</sub></td><td>NaHCO<sub>3</sub> (2)</td><td>0</td><td>0</td></tr><tr><td>13</td><td>[RuCl<sub>2</sub>(p-cymene)]<sub>2</sub> (5)</td><td>AgSbF<sub>6</sub><br>(15 mol% +<br>KOAc (2))</td><td>100</td><td>86 (72)</td></tr><tr><td>14<sup>c</sup></td><td>[RhCl(COD)]<sub>2</sub></td><td>NaHCO<sub>3</sub> (2)</td><td>0</td><td>0</td></tr><tr><td>15<sup>f</sup></td><td>[RhCl(COD)]<sub>2</sub></td><td>NaHCO<sub>3</sub> (2)</td><td>0</td><td>0</td></tr><tr><td>16<sup>f</sup></td><td>[Ru(p-cymene)Cl<sub>2</sub>]<sub>2</sub> (5)</td><td>AgSbF<sub>6</sub><br>(15 mol% +<br>KOAc (2))</td><td>0</td><td>0</td></tr></tbody></table>

Next, we turned our attention to the scope of the reaction (Scheme 1). PhenCarPhos (1a) was alkylated with ethyl (2b), benzyl (2c) and eicosyl (2d) acrylates providing the carbazolyl-derived phosphine-ester ligands **3b-3d** in 85-94% yields. Ru(II) conditions afford the same products, albeit in slightly lower yields. We also incorporated enantiopure L-menthol acrylate unit on this phosphine scaffold to afford the chiral phosphine-ester **3e** in 89% of yield. We also coupled **1a** with acrylamides using either Rh or Ru to give phosphine-amide hybrid ligands **3f** and **3g** in 56% and 70% yield, respectively.

<footnote><sup>a</sup> determined by <sup>31</sup>P NMR using PPh<sub>3</sub> as internal standard, isolated yield is shown in parentheses; <sup>b</sup> in 1,4-dioxane; <sup>c</sup> in DMF; <sup>d</sup> in 1,2-dichloroethane; <sup>e</sup> reaction from **3a**; <sup>f</sup> reaction from (N-(2-(dicyclohexylphosphaneyl)phenyl)carbazole</footnote>
The conditions tolerate a chloro-substituent at the *para*-position of the PPh₂ group, providing phosphine-amide ligand **3h** and phosphine-ester ligand **3i** in 65% (on 2 mmol scale) and 86% yield, respectively. From 9-(2-(diphenylphosphaneyl)-5-chloro-4-methylphenyl)carbazole (1c) and 9-(2-(diphenylphosphaneyl)-4-(trifluoromethyl)phenyl)carbazole (1d), phosphine-ester ligands **3j** and **3k** was isolated in moderate yields. There is no major influence to introduce substituents, like tert-butyl, on the carbazolyl unit at C3 and C6 positions, as alkylated carbazolylphosphine **3l** was isolated in 73% yield. This alkylation method was also transferable to the modification of indolyl-derived phosphine (1f), resulting in **3m**. However, no reaction occurred when the carbazolyl part was replaced by phenoxazinyl unit. The size of the *N*-heterocycles might explain this lack of reactivity: C–H bond alkylation is limited to using 5-membered ring *N*-heterocycles due to the possible formation of conformationally constrained conformational strengths 7-membered rodacycle intermediates.

<figure><img src="image_5.png" /></figure>

Reaction conditions: **1** (0.2 mmol), **2** (0.24 mmol), [RhCl(COD)]₂ (2.5 mol %), NaHCO₃ (0.4 mmol), toluene (1.0 mL) at 140 °C for 16 h. ¹ (0.2 mmol), **2** (0.4 mmol), RuCl₂(p-cymene)]₂ (5 mol %), AgSbF₅ (15 mol %), KOAc (2 equiv.), toluene (1.0 mL) at 140 °C for 24 h. ² on 2 mmol scale.

**Scheme 1. Scope of Rh(I)-Catalyzed C–H Bond Alkylation of Carbazolyl-Derived Phosphine Ligands**

Over the last decades, the development of eco-friendly catalytic CO₂-fixation reactions has garnered a new vision for the economy of CO₂ from a waste product toward an abundant, nontoxic C1 feedstock for constructing synthetic intermediates.¹⁶ In line with our previous discovery on upgrading catalytic activities of biarylphosphines for Pd-catalyzed carboxylation of aryl bromides with CO₂ ⁹A we firstly investigated the effect of C–H bond alkylation of PhenCarPhos in Pd-catalyzed
synthesis of oxazolidinones, which are essential building blocks, using CO2 and propargylic amines. Several reports on carboxylation of propargylamines or aminoalcohols with CO2 to access oxazolidinones have appeared during the last decade.17 In most of the cases, *p*-acid catalysis (silver<sup>18</sup> or gold<sup>19</sup>) was employed with a stoichiometric amount of organic bases. In 2017, Bourissou and co-workers carried out this transformation under base-free conditions using a well-defined SCS indenediide Pd complex.20 Moreover, in all cases, DMSO is employed as the solvent. We resonated that PhenCarPhos may be a better ligand, as the carbazolyl unit will play the role of a basic residue. Therefore, we elevated our library of phosphines for the coupling of *N*-benzyl-3-phenylprop-2-yn-1-amine (4) in the presence of CO2 (1 atm) in a water media using 0.5 mol% Pd(OAc)2(Scheme 2, green). No reaction occurred in the absence of phosphine, while a low yield of 36% was obtained with PPh3. Interestingly, a better yield of 48% was obtained with PhenCarPhos. Chasing the best ligand for this carboxylation-cyclization reaction, we next evaluated the effect of modifications on the PhenCarPhos scaffold. The phosphine-ester hybrid ligands **3a**, **3c-e** exhibited higher catalytic activities for the formation of **5a** than the parent phosphine. The best modification was with *n*-butyl acrylate or benzyl acrylate. Reactions performed with phosphine-amide hybrid ligands **3f** and **3g** were less performant. Then, we demonstrate that there the incorporation of Cl substituent on *N*-aryl group at the *para*-position of PPh2 group slightly increased the yield of **5a** (52% with **3i** or **3j**), while the introduction of CF3 group has a deleterious effect (42% with **3k**). Next, we studied the effect of the heterocycle; the substitution of carbazolyl by its 3,6-di-tert-butyl congener did not a significantly impact. However, the installation of the 2-phenylindolyl group improves the catalytic performance, as with phosphine **1f**, oxazolidinone **5a** was isolated in 66% yield. Finally, a spectacular catalytic property's upgrading was observed through the C–H bond alkylation of **1f** with *n*-butyl acrylate, as phosphine-ester hybrid ligand **3m** gives **5a** in 91% yield.

As the upgrading of carbazolyl-phosphines through Rh(I)-catalyzed C–H bond alkylation morphs moderate active ligand into very active bifunctional phosphine in Pd-catalyzed carboxylation-cyclization reaction, we also investigate this strategy in Pd-catalyzed 3-component carboxylation-cyclization-cross-coupling reaction, which was initially developed by Nevado and co-workers using well-defined [PdCl2(dppf)] catalyst.21 This reaction prepares functionalized oxazolidinones from CO2, propargylamines, and aryl iodides. Propargylamine **4a**, iodoanisole(**6a**) in the presence of *t*-BuONa (1.5 equiv) and Pd(OAc)2 (0.5 mol%) in DMSO at 60 °C were chosen as standard conditions to evaluate (alkylated) carbazolyl-phosphines (Scheme 2, blue). Again, PhenCarPhos outperformed PPh3. Delving into the screening of the effect post-modification of PhenCarPhos and then scaffold revealed that the best ligand for this 3-component reaction should hold an *N*--(2-(*di*)isopropylamino)ethyl), a carbazolyl and a chloro groups. Indeed, the phosphine **3h**, specifically designed for this reaction, allowed to isolate **7a** in 77% yield.
<figure><img src="image_6.png" /><figcaption>**Scheme 2.** Catalytic Activities of Modified Phosphines in (1) Pd-Catalyzed Carboxylation-Cyclization of Propargylamine (4a) with CO₂ & (2) Pd-Catalyzed 3-Component Carboxylation-Cyclization-Cross-Coupling Reaction</figcaption></figure>

With the optimized ligand in hand, we explored the scope of aryl iodides under these conditions (Scheme 2). Reactions with aryl iodide bearing electron-donating or withdrawing groups give the corresponding oxazolidinones 7b-e in good to excellent yields. However, the reaction with bromobenzene or chlorobenzene was unsuccessful, leading only to the formation of 5a.

<figure><img src="image_7.png" /><figcaption>**Scheme 3.** Scope of Pd-catalyzed 3-Component Carboxylation-Cyclization-Cross-Coupling Reaction using 3m</figcaption></figure>

In summary, we reported the first example of the C–H bond functionalization of carbazolyl-derived phosphines (PhenCar-Phos). This C–H bond alkylation using activated alkenes occurs at the C1-position of the carbazolyl ring through P¹¹I⁻-assisted C–H bond cleavage using [RhCl(COD)]₂. This direct approach paves the way to quickly preparing a library of new phosphine hybrid ligands. Some of them have outperformed their parent ones in Pd-catalyzed CO₂-fixations reactions to prepare oxazolidinones from alkynes and (aryl iodides). Together these results suggest that a better solubility might explain
the upgrading of catalytic performances after incorporating an ester group. Besides, the introduction of an amino group
might participate in the stabilization of active Pd catalytic species or interact with CO2. Another explanation could be that
introducing an alkyl group on the carbazole could prevent the cyclometallation with palladium like the *i*-Pr group in the
XPhos ligand. This late-stage functionalization of phosphines will help to design new phosphines to discover novel reac-
tivity, especially for CO2-fixation reactions.

ACKNOWLEDGMENT

We thank the CNRS, UR1, Agence Nationale de la Recherche (Grant No. ANR-20-CE07-0019-01) for providing financial support, and Z.Z. thanks to the China Scholarship Council (CSC) for his Ph.D. grant (Grant No. 201706780007). We also thank Mettalor for their generous gift of palladium acetate.

REFERENCES

(1) (a) Martin, R.; Buchwald, S. L. Palladium-Catalyzed Suzuki–Miyaura Cross-Coupling Reactions Employing Dialkylbiaryl Phosphine Ligands. *Acc. Chem. Res.* **2008**, *41*, 1461-1473. (b) Adrio, L. A.; Hii, K. K. Application of Phosphine Ligands in Organic Synthesis. *Organomet. Chem* **2009**, *35*, 62-92. (c) Clevenger, A. L.; Stolley, R. M.; Aderibigbe, J.; Louie, J. Trends in the Usage of Bidentate Phosphines as Ligands in Nickel Catalysis. *Chem. Rev.* **2020**, *120*, 6124-6196.

(2) Shelby, Q.; Kataoka, N.; Mann, G.; Hartwig, J. Unusual in Situ Ligand Modification to Generate a Catalyst for Room Temperature Aromatic C–O Bond Formation. *J. Am. Chem. Soc.* **2000**, *122*, 10718–10719.

(3) Zhang, Z.; Dixneuf, P. H.; Soulé, J.-F. Late Stage Modifications of P-containing Ligands using Transition-Metal-Catalyzed C-H Bond Functionalisation. *Chem. Commun.* **2018**, *54*, 7265-7280.

(4) (a) Wen, J.; Wang, D.; Qian, J.; Wang, D.; Zhu, C.; Zhao, Y.; Shi, Z. Rhodium-Catalyzed PIII-Directed ortho-C–H Borylation of Arylphosphines. *Angew. Chem. Int. Ed.* **2019**, *58*, 2078-2082. (b) Fukuda, K.; Iwasawa, N.; Takaya, J. Ruthenium-Catalyzed ortho C–H Borylation of Arylphosphines. *Angew. Chem. Int. Ed.* **2019**, *58*, 2850-2853. (c) Homma, Y.; Fukuda, K.; Iwasawa, N.; Takaya, J. Ruthenium-Catalyzed Regio- and Site-Selective *ortho* C–H Borylation of Phenol Derivatives. *Chem. Commun.* **2020**, *56*, 10710–10713.

(5) Wen, J.; Dong, B.; Zhu, J.; Zhao, Y.; Shi, Z. Revealing Silylation of C(sp2)/C(sp3)–H Bonds in Arylphosphines by Ruthenium Catalysis. *Angew. Chem. Int. Ed.* **2020**, *59*, 10909–10912.

(6) Wang, D.; Li, M.; Shuang, C.; Liang, Y.; Zhao, Y.; Wang, M.; Shi, Z. Rhodium-Catalyzed Selective Direct Arylation of Phosphines with Aryl Bromides. *Nat. Commun.* **2022**, *13*, 2934.

(7) Wright, S. E.; Richardson-Solorzano, S.; Stewart, T. N.; Miller, C. D.; Morris, K. C.; Daley, C. J. A.; Clark, T. B. Accessing Ambiphilic Phosphine Boronates through C–H Borylation by an Unforeseen Cationic Iridium Complex. *Angew. Chem. Int. Ed.* **2019**, *58*, 2834–2838.

(8) (a) Wang, D.; Zhao, Y.; Yuan, C.; Wen, J.; Zhao, Y.; Shi, Z. Rhodium(II)-Catalyzed Dehydrogenative Silylation of Biaryl-Type Monophosphines with Hydrosilanes. *Angew. Chem. Int. Ed.* **2019**, *58*, 12529-12533. (b) Wang, L.-N.; Tang, P.-T.; Li, M.; Li, J.-W.; Liu, Y.-J.; Zeng, M.-H. Double Ligands Enabled Ruthenium Catalyzed ortho-C–H Arylation of Dialkyl Biarylphosphines: Straight and Economic Synthesis of Highly Steric and Electron-Rich Aryl-Substituted Buchwald-Type Phosphines. *Adv. Synth. Catal.* **2021**, *363*, 2843-2849. (c) Zhang, N.-J.; Ma, W.-T.; Li, J.-W.; Liu, Y.-J.; Zeng, M.-H. Solvent-Free Ruthenium-Catalyzed Direct Coupling of Phosphines and Aryl Chlorides via C–H Activation: An Efficient and Straight Access to Aryl-Substituted Biarylphosphines. *Asian J. Org. Chem.* **2021**, *10*, 1113-1116.

(9) (a) Zhang, Z.; Roisnel, T.; Dixneuf, P. H.; Soulé, J.-F. Rh(I)-Catalyzed P(III) -Directed C-H Bond Alkylation: Design of Multifunctional Phosphines for Carboxylation of Aryl Bromides with Carbon Dioxide. *Angew. Chem. Int. Ed.* **2019**, *58*, 14110-
14114. (b) Li, G.; An, J.; Jia, C.; Yan, B.; Zhong, L.; Wang, J.; Yang, S. *m*-CAr-H Bond Alkylations and Difluoromethylation of Tertiary Phosphines Using a Ruthenium Catalyst. *Org. Lett.* **2020**, *22*, 9450-9455. (c) Li, J.-W.; Wang, L.-N.; Li, M.; Tang, P.-T.; Zhang, N.-J.; Li, T.; Luo, X.-P.; Kurmoo, M.; Liu, Y.-J.; Zeng, M.-H. Late-Stage Modification of Tertiary Phosphines via Ruthenium(II)-Catalyzed C–H Alkylation. *Org. Lett.* **2020**, *22*, 1331-1335. (d) Li, M.; Tao, J.-Y.; Wang, L.-N.; Li, J.-W.; Liu, Y.-J.; Zeng, M.-H. Construction of Bulky Ligand Libraries by Ru(II)-Catalyzed P(III)-Assisted ortho-C–H Secondary Alkylation. *J. Org. Chem.* **2021**, *86*, 11915-11925. (e) Xu, H.-B.; Chen, Y.-J.; Chai, X.-Y.; Yang, J.-H.; Xu, Y.-J.; Dong, L. Ruthenium-Catalyzed PIII-Directed Remote ε-C–H Alkylation of Phosphines. *Org. Lett.* **2021**, *23*, 2052-2056.

(10) (a) Zhang, Z.; Cordier, M.; Dixneuf, P. H.; Soulé, J.-F. Late-Stage Diversification of Biarylphosphines through Rhodium(I)-Catalyzed C–H Bond Alkenylation with Internal Alkynes. *Org. Lett.* **2020**, *22*, 5936-5940. (b) Luo, H.; Wang, D.; Wang, M.; Shi, Z. Rhodium-Catalyzed, Phosphorus(III)-Directed Hydroarylation of Internal Alkynes: Facile and Efficient Access to New Phosphine Ligands. *Synlett* **2021**, *33*, 351-356.

(11) Dong, B.; Qian, J.; Li, M.; Wang, Z.-J.; Wang, M.; Wang, D.; Yuan, C.; Han, Y.; Zhao, Y.; Shi, Z. External Oxidant-Compatible Phosphorus(III)-Directed Site-Selective C–H Carbonylation. *Sci. Adv.* **2020**, *6*, eabd1378.

(12) Luo, X.; Yuan, J.; Yue, C.-D.; Zhang, Z.-Y.; Chen, J.; Yu, G.-A.; Che, C.-M. Synthesis of peri-Substituted (Naphthalen-1-yl)phosphine Ligands by Rhodium(I)-Catalyzed Phosphine-Directed C–H Arylation. *Org. Lett.* **2018**, *20*, 1810-1814.

(13) (a) Fu, Y.; Chen, C.-H.; Huang, M.-G.; Tao, J.-Y.; Peng, X.; Xu, H.-B.; Liu, Y.-J.; Zeng, M.-H. Remote C5-Selective Functionalization of Naphthalene Enabled by P–Ru–C Bond-Directed δ-Activation. *ACS Catal.* **2022**, *5036-5047*. (b) Ma, W.-T.; Huang, M.-G.; Fu, Y.; Wang, Z.-H.; Tao, J.-Y.; Li, J.-W.; Liu, Y.-J.; Zeng, M.-H. Ru(II)-catalyzed P(III)-assisted C8-alkylation of naphthphosphines. *Chem. Commun.* **2022**, *58*, 7152-7155.

(14) Zhang, Z.; Durand, N.; Soulé, J.-F. How Rhodium(I)-Catalyzed Phosphorus(III)-Directed C–H Bond Functionalizations Can Improve the Catalytic Activities of Phosphines. *Synlett* **2022**, *33*, 705-712.

(15) (a) To, S. C.; Kwong, F. Y. Highly Efficient Carbazolyl-Derived Phosphine Ligands: Application to Sterically Hindered Biaryl Couplings. *Chem. Commun.* **2011**, *47*, 5079-5081. (b) Fu, W. C.; Zhou, Z.; Kwong, F. Y. Preparation of a Highly Congested Carbazoyl-Derived P,N-Type Phosphine Ligand for Acetone Monoarylations. *Organometallics* **2016**, *35*, 1553-1558. (c) Fu, W. C.; Zhou, Z.; Kwong, F. Y. A Benzo[c]carbazolyl-based Phosphine Ligand for Pd-Catalyzed Tetra-ortho-Substituted Biaryl Syntheses. *Org. Chem. Front.* **2016**, *3*, 273-276. (d) Leung, M. P.; Choy, P. Y.; Lai, W. I.; Gan, K. B.; Kwong, F. Y. Facile Assembly of Carbazolyl-Derived Phosphine Ligands and Their Applications in Palladium-Catalyzed Sterically Hindered Arylation Processes. *Org. Process Res. Dev.* **2019**, *23*, 1602-1609. (e) Lai, W. I.; Leung, M. P.; Choy, P. Y.; Kwong, F. Y. Sterically Hindered Amination of Aryl Chlorides Catalyzed by a New Carbazolyl-Derived P, N-Ligand-Composed Palladium Complex. *Synthesis* **2019**, *51*, 2678-2686. (f) Gan, K. B.; Zhong, R.-L.; Zhang, Z.-W.; Kwong, F. Y. Atropisomeric Phosphine Ligands Bearing C–N Axial Chirality: Applications in Enantioselective Suzuki–Miyaura Cross-Coupling Towards the Assembly of Tetra-ortho-Substituted Biaryls. *J. Am. Chem. Soc.* **2022**, *144*, 14864-14873.

(16) (a) Aresta, M.; Dibenedetto, A. Utilisation of CO2 as a Chemical Feedstock: Opportunities and Challenges. *Dalton Trans.* **2007**, 2975-2992. (b) Sakakura, T.; Choi, J.-C.; Yasuda, H. Transformation of Carbon Dioxide. *Chem. Rev.* **2007**, *107*, 2365-2387.

(c) Cokoja, M.; Bruckmeier, C.; Rieger, B.; Herrmann, W. A.; Kühn, F. E. Transformation of Carbon Dioxide with Homogeneous Transition-Metal Catalysts: a Molecular Solution to a Global Challenge? *Angew. Chem. Int. Ed.* **2011**, *50*, 8510-8537. (d) Fiorani, G.; Guo, W.; Kleij, A. W. Sustainable Conversion of Carbon Dioxide: the Advent of Organocatalysis. *Green Chem.* **2015**, *17*, 1375-1389. (e) Börjesson, M.; Moragas, T.; Gallego, D.; Martin, R. Metal-Catalyzed Carboxylation of Organic (Pseudo)halides with CO2. *ACS Catal.* **2016**, *6*, 6739-6749. (f) Artz, J.; Müller, T. E.; Thenert, K.; Kleinekorte, J.; Meys, R.; Sternberg, A.; Bardow, A.; Leitner, W. Sustainable Conversion of Carbon Dioxide: An Integrated Review of Catalysis and Life Cycle Assessment. *Chem. Rev.* **2018**, *118*, 434-504. (g) Dabral, S.; Schaub, T. The Use of Carbon Dioxide (CO2) as a Building Block in Organic Synthesis from an Industrial Perspective. *Adv. Synth. Catal.* **2019**, *361*, 223-246.
(17) (a) Yu, B.; He, L. N. Upgrading Carbon Dioxide by Incorporation into Heterocycles. *ChemSuschem* **2015**, *8*, 52-62. (b) Arshadi, S.; Vessally, E.; Sobati, M.; Hosseinian, A.; Bekhradnia, A. Chemical Fixation of CO2 to N-Propargylamines: A Straightforward Route to 2-Oxazolidinones. *J. CO2 Util.* **2017**, *19*, 120-129. (c) Zhang, Z.; Ye, J. H.; Wu, D. S.; Zhou, Y. Q.; Yu, D. G. Synthesis of Oxazolidin-2-ones from Unsaturated Amines with CO2 by Using Homogeneous Catalysis. *Chem. Asian J.* **2018**, *13*, 2292-2306.

(18) (a) Shunsuke, Y.; Kosuke, F.; Satoshi, K.; Tohru, Y. Silver-Catalyzed Preparation of Oxazolidinones from Carbon Dioxide and Propargylic Amines. *Chem. Lett.* **2009**, *38*, 786-787. (b) Yoshida, M.; Mizuguchi, T.; Shishido, K. Synthesis of Oxazolidinones by Efficient Fixation of Atmospheric CO2 with Propargylic Amines by using a Silver/1, 8-Diazabicyclo[5.4.0] undec-7-ene (DBU) Dual-Catalyst System. *Chem. Eur. J.* **2012**, *18*, 15578-15581. (c) Ishida, T.; Kikuchi, S.; Tsubo, T.; Yamada, T. Silver-Catalyzed Incorporation of Carbon Dioxide into *o*-Alkynylaniline Derivatives. *Org. Lett.* **2013**, *15*, 848-851. (d) Sekine, K.; Kobayashi, R.; Yamada, T. Silver-Catalyzed Three-component Reaction of Propargylic Amines, Carbon Dioxide, and N-Iodosuccinimide for Stereoselective Preparation of (E)-Iodovinyloxazolidinones. *Chem. Lett.* **2015**, *44*, 1407-1409. (e) Song, Q. W.; He, L. N. Robust Silver(I) Catalyst for the Carboxylative Cyclization of Propargylic Alcohols with Carbon Dioxide under Ambient Conditions. *Adv. Synth. Catal.* **2016**, *358*, 1251-1258. (f) Gao, X.-T.; Gan, C.-C.; Liu, S.-Y.; Zhou, F.; Wu, H.-H.; Zhou, J. Utilization of CO2 as a C1 Building Block in a Tandem Asymmetric A3 Coupling-Carboxylative Cyclization Sequence to 2-Oxazolidinones. *ACS Catal.* **2017**, *7*, 8588-8593. (g) Dabral, S.; Bayarmagnai, B.; Hermsen, M.; Schießl, J.; Mormul, V.; Hashmi, A. S. K.; Schaub, T. Silver-Catalyzed Carboxylative Cyclization of Primary Propargyl Alcohols with CO2. *Org. Lett.* **2019**, *21*, 1422-1425.

(19) (a) Hase, S.; Kayaki, Y.; Ikariya, T. NHC-Gold(I) Complexes as Effective Catalysts for the Carboxylative Cyclization of Propargylamines with Carbon Dioxide. *Organometallics* **2013**, *32*, 5285-5288. (b) Hase, S.; Kayaki, Y.; Ikariya, T. Mechanistic Aspects of the Carboxylative Cyclization of Propargylamines and Carbon Dioxide Catalyzed by Gold(I) Complexes Bearing an N-Heterocyclic Carbene Ligand. *ACS Catal.* **2015**, *5*, 5135-5140. (c) Fujita, K.-i.; Inoue, K.; Sato, J.; Tsuchimoto, T.; Yasuda, H. Carboxylative Cyclization of Propargylic Amines with CO2 Catalyzed by Dendritic N-Heterocyclic Carbene-Gold(I) Complexes. *Tetrahedron* **2016**, *72*, 1205-1212.

(20) Brunel, P.; Monot, J.; Kefalidis, C. E.; Maron, L.; Martin-Vaca, B.; Bourissou, D. Valorization of CO2: Preparation of 2-Oxazolidinones by Metal-Ligand Cooperative Catalysis with SCS Indenediide Pd Complexes. *ACS Catal.* **2017**, *7*, 2652-2660.

(21) (a) García-Domínguez, P.; Fehr, L.; Rusconi, G.; Nevado, C. Palladium-Catalyzed Incorporation of Atmospheric CO2: Efficient Synthesis of Functionalized Oxazolidinones. *Chem. Sci.* **2016**, *7*, 3914-3918. (b) Zhou, C.; Dong, Y.; Yu, J.-T.; Sun, S.; Cheng, J. Palladium/Copper-Catalyzed Multicomponent Reactions of Propargylic Amides, Halohydrocarbons and CO2 Toward Functionalized Oxazolidine-2,4-diones. *Chem. Commun.* **2019**, *55*, 13685-13688.