双磷配体的合成及铑—双磷配体催化剂为混合辛烯氢甲酰化反应的催？…

合成了具有不同电子效应的３种双膦配体。其给电子性为Ｐｈ２Ｐ（ＣＨ２）４ＰＰｈ２〉Ｐｈ２Ｐ（Ｏ）（ＣＨ２）４ＰＰｈ２〉Ｐｈ２Ｐ（Ｏ）（ＣＨ２）４Ｐ（Ｏ）Ｐｈ２。这３种配体与醋酸铑二聚体配合物构成的催化剂,在混合辛烯的均相氢甲酰化反应中表现出的活性和选择性与配体给电子性强弱的次序完全相反。我们认为,具有弱配位性的「Ｒｈ（ＣＨ３ＣＯＯ）２」２Ｐｈ２Ｐ（Ｏ）（ＣＨ２）４Ｐ（Ｏ）Ｐｈ２催化体系,因其形成的活     

担载Rh／Al2O3催化剂表面吸附态的加压原位红外光谱表征

应用加温加压气固多相催化原位红外光谱反应器,在Ｈ２／ＣＯ＝２：１（ｍｏｌ）、０．５￣５．０ＭＰａ和２０￣３００℃的接近ＣＯ＋Ｈ２工业反应条件下,考察了还原态和氧化态Ｒｈ／Ａｌ２Ｏ３催化剂表面ＣＯ吸附态,关联了吸附态与催化剂活性的关系。实验结果表明,还原态的Ｒｈ／Ａｌ２Ｏ３催化剂一氧化碳加氢生成烃类,其催化剂表面存在三种ＣＯ吸附态：线式Ｒｈ（ＣＯ）,孪生式Ｒｈ（ＣＯ）２和桥式Ｒｈ２ＣＯ。在常温常压下     

SiO_2负载的Pt－M、Rh－M异双核络合物催化剂催化CO_2氢化反应

考察了ＳｉＯ２负载的（ＰＰｈ３）２ＨＰｔ（μ－ＣＯ）（μ－ＰＰｈ２）Ｍ（ＣＯ）４和（ｄｐｐｅ）Ｒｈ（μ－ＣＯ）２Ｍ（ＣＯ）３（Ｍ＝Ｃｒ、Ｍｏ、Ｗ；ｄｐｐｅ＝Ｐｈ２Ｐ（ＣＨ２）２ＰＰｈ２）异双核络合物催化剂催化ＣＯ２氢化反应的活性和选择性．两者皆表现出较高的催化活性和含氧化合物选择性，而前者比后者更好．     

烯烃氢甲酰化反应的原位红外光谱表征

将原位红外光谱表征方法用于探测Ｒｈ－ＰＢｕ３－ＥｔＯＵ体系中的庚烯氢甲酰化制辛醇的反应历程及活性物种的形成过程和Ａｌ２Ｏ３为载体的Ｒｈ－ＰＰｈ３催化剂活性物种的活化及氧化失活过程的研究。     

NO在碳纳米管(CNTs),Rh/CNTs,Rh/Al_2O_3上的分解(英文)

甲烷在预还原的ＬａＣｏＯ３催化剂上分解生成碳纳米管（ＣＮＴｓ）。研究了稳态下ＮＯ在ＣＮＴｓ,Ｒｈ／ＣＮＴｓ,Ｒｈ／Ａ１２Ｏ３上的分解,温度区间为５７３Ｋ～９７３Ｋ,原料气为６０００ｐｐｍ的ＮＯ,Ｈｅ为平衡气。程序升温还原结果表明：（１）Ｒｈ的负载显著降低了ＣＮＴｓ的氢吸收量;（２）负载于ＣＮＴｓ上的Ｒｈ比负载于Ａ１２Ｏ３上的Ｒｈ更易还原。在５７３Ｋ时ＮＯ即能与预还原后的ＣＮＴｓ,Ｒｈ／ＣＮＴＳ,Ｒｈ／Ａｌ２Ｏ３中存储的氢反应;随着氢的消耗,反应活性逐渐降低,当储存的氢消耗完后,ＮＯ的直接催化反应发生。在８７３ Ｋ及以上,Ｒｈ／ＣＮＴｓ中的ＣＮＴｓ能彼ＮＯ分解产生的氧氧化为ＣＯ。在９７３Ｋ时,ＮＯ在ＣＮＴｓ上几乎能１００％分解,连续反应１５０ｍｉｎ后其反应活性不降低,且未观察到ＣＯ或ＣＯ２的生成。在９７３Ｋ时ＣＮＴｓ本身可作为ＮＯ分解的催化剂,这是一个非常有意义的结果。     

Rh/SiO_2催化剂上甲烷部分氧化制合成气反应机理的研究(英文)

运用ＴＰＳＲ、ＴＲ－ＦＴＩＲ和化学捕获技术（ＣＨ３Ｉ作捕获剂）,探讨了Ｒｈ／ＳｉＯ２催化剂上的ＰＯＭ反应机理,由此提出热分解氧化机理,认为ＣＨｘ（ｘ＝１～３）和ＣＨｘＯ（ｘ＝１～３）可能是反应物种。     

铑基催化剂催化CO加氢合成乙醇

用溶胶－凝胶法合成了系列Ｒｈ／ＣｅＯ２／ＳｉＯ２,用浸渍法合成了Ｒｈ／ＣｅＯ２（Ｉ）,并用Ｈ２化学吸附ＸＰＳ,ＴＰＲ等技术进行了表征,结果表明,在所用的实验条件下,铑完全还原,而ＣｅＯ２未还原,Ｒｈ－ＣｅＯ２间存在强相互作用,在常压ＣＯ加氢反应中,未加氧化物促进剂的Ｒｈ／ＳｉＯ２即能催化乙醛的生成,但产物中仅有极少量甲醇和乙醇,随着ＣｅＯ２含量的增加,催化剂的活性显著降低、ＣｅＯ２的加入降低了乙醛     

KI-醚类催化剂催化二氧化碳和环氧乙烷合成碳酸乙烯酯反应研究

合成了５个含有金属铁的环醚Ｆｅ（ＣＯ）３Ｌ（Ｌ１＝Ｐｈ２Ｐ（ＣＨ２ＣＨ２Ｏ）２ＣＨ２ＣＨ２ＰＰｈ２，Ｌ２＝Ｐｈ２Ｐ（ＣＨ２ＣＨ２Ｏ）４ＣＨ２ＣＨ２ＰＰｈ２，Ｌ３＝ＯＰｈ［（ＯＣＨ２ＣＨ２）ＰＰｈ２］２，Ｌ４＝ＯＰｈ［ＯＣＨ２ＣＨ２）２ＰＰｈ２］２）和［Ｆｅ（ＣＯ３）］２Ｌ５（Ｌ５＝［Ｐｈ２ＰＣＨ２ＣＨ２ＯＣＨ２ＣＨ２ＰＰｈ２］２）．对它们进行了元素分析，并用红外光谱和核磁共振谱进行了结构表征．用ＫＩ＋醚类为催化剂，催化二氧化碳与环氧乙烷反应生成碳酸乙烯酯，反应选择性大于９６．９％．催化机理为碱催化，催化剂的活性受醚的影响．能和Ｋ＋形成稳定配合物的醚可提高催化剂的活性．含金属铁的环醚和普通醚类相似，可以和钾离子作用，提高阴离子的亲核催化性能．     

甲烷部分氧化制合成气：Ⅱ.载体的影响

本文对三种催化剂（１％Ｒｈ／ｍ－Ｓｍ２Ｏ３，１％Ｒｈ／ｃ－Ｓｍ２Ｏ３）在甲烷部分氧化反应的催化活性与一氧化碳和氢的选择性作了比较。用二氧化碳的程序升温脱附测试了载体的相对碱性强弱；并用同位素交换反应测定了载体和负载型铑催化剂对甲烷分子中Ｃ－Ｈ和氧气分子中Ｏ－Ｏ键的解离活化能力，虽然催化活性高低与载体的碱性及解离活化能力之间没有直接的对应关系，但通过载体对反应活性影响的研究能揭示一般的规律，对研制甲     

负载水溶性铑－膦配合物催化1－己烯氢甲酰化反应的研究

将水溶性铑－膦配合物Ｒｈｃｉ（ＣＯ）（ＴＰＰＴＳ）＿２（ＴＰＰＴＳ：Ｐ－（ｍ－Ｃ＿６Ｈ＿４ＳＯ＿３Ｎａ）＿３）负载于扩孔硅胶上，制成负载水相催化剂（ＳＡＰＣ），在高压反应釜中研究其催化１－己烯氢甲酰化的性能。结果表明，催化剂的水含量对其活性影响很大，在一较窄的水含量范围内（２５—３５ｗｔ％），催化剂活性急剧增大，且存在一极大值，表现出水膜催化剂的特性。反应温度、总压和ＣＯ／Ｈ＿２分压、Ｒｈ／Ｐ比的影响，与使用烃溶性能。三苯膦络合催化剂时有类似规律，溶剂的影响不明显，实验证明，ＳＡＰＣ具有良好催化活性，ＳｉＯ＿２上负载的铑配合物不会被原料和产物洗提而造成流失，有利于催化剂的稳定和重复使用。     

Reactivity of rhodium-triflate complexes with diphenylsilane: evidence for silylene intermediacy in stoichiometric and catalytic reactions

Addition of Ph2SiH2 to [Rh(iPr3P)2(OTf)] (1) yielded the thermally unstable RhIII adduct [Rh(iPr3P)2(OTf)(H)(SiPh2H)] (2), which decomposed to [Rh(iPr3P)2(H)2(OTf)] (3), liberating (unobserved) silylene. The silylene was trapped by 1, resulting in the RhI-silyl complex [Rh(iPr3P)2(SiPh2OTf)]. Complex 3 was converted to 2 by addition of diphenylsilane, providing a basis for a possible catalytic cycle. The last reaction did not involve a RhI intermediate, as shown by a labeling study. Complex 1 catalyzed the dehydrogenative coupling of Ph2SiH2 to Ph2HSi--SiHPh2. A mechanism involving a silylene intermediate in this catalytic cycle is proposed. The mechanism is supported by complete lack of catalysis in the case of the tertiary silanes Ph2MeSiH and PhMe2SiH, and by a study of individual steps of the catalytic cycle. The outcome of the reaction of Ph2SiH2 with styrene in the presence of 1 depends on the complex/substrate ratio; under stoichiometric conditions olefin hydrogenation prevailed over hydrosilylation, whereas with excess of substrates hydrosilylation prevailed. Catalytic hydrosilylation resulted in double addition giving Ph2Si(CH2CH2Ph)2. Mechanistic aspects of the reported processes are discussed, and a new hydrosilylation mechanism based on silylene intermediacy is proposed.     

Cu(I)-catalyzed hetero-Diels-Alder reaction between Danishefsky-type siloxy dienes and ketones

A general catalytic method for the hetero-Diels-Alder reaction between Danishefsky-type siloxy dienes and ketones was developed. Optimum results were produced with a catalyst generated from CuOTf x (C6H6)1/2 and TBAT with Ph 3PO as the catalytic additive. This reaction was extended to an asymmetric variant, using a Cu(I)-Walphos catalyst.     

Synthesis and characterization of indium and thallium immobilized on isonicotinamide‐functionalized mesoporous MCM‐41: Two novel and highly active heterogeneous catalysts for selective oxidation of sulfides and thiols to their corresponding sulfoxides and disulfides

Two highly ordered isonicotinamide (INA)‐functionalized mesoporous MCM‐41 materials supporting indium and thallium (MCM‐41‐INA‐In and MCM‐41‐INA‐Tl) have been developed using a covalent grafting method. A surface functionalization method has been applied to prepare Cl‐modified mesoporous MCM‐41 material. Condensation of this Cl‐functionalized MCM‐41 with INA leads to the formation of MCM‐41‐INA. The reaction of MCM‐41‐INA with In(NO₃)₃ or Tl(NO₃)₃ leads to the formation of MCM‐41‐INA‐In and MCM‐41‐INA‐Tl catalysts. The resulting materials were characterized using various techniques. These MCM‐41‐INA‐In and MCM‐41‐INA‐Tl catalysts show excellent catalytic performance in the selective oxidation of sulfides and thiols to their corresponding sulfoxides and disulfides. Finally, it is found that the anchored indium and thallium do not leach out from the surface of the mesoporous catalysts during reaction and the catalysts can be reused for seven repeat reaction runs without considerable loss of catalytic performance.     

The F/Ph rearrangement reaction of [(Ph3P)3RhF], the fluoride congener of Wilkinson's catalyst

The fluoride congener of Wilkinson's catalyst, [(Ph(3)P)(3)RhF] (1), has been synthesized and fully characterized. Unlike Wilkinson's catalyst, 1 easily activates the inert C-Cl bond of ArCl (Ar = Ph, p-tolyl) under mild conditions (3 h at 80 degrees C) to produce trans-[(Ph(3)P)(2)Rh(Ph(2)PF)(Cl)] (2) and ArPh as a result of C-Cl, Rh-F, and P-C bond cleavage and C-C, Rh-Cl, and P-F bond formation. In benzene (2-3 h at 80 degrees C), 1 decomposes to a 1:1 mixture of trans-[(Ph(3)P)(2)Rh(Ph(2)PF)(F)] (3) and the cyclometalated complex [(Ph(3)P)(2)Rh(Ph(2)PC(6)H(4))] (4). Both the chloroarene activation and the thermal decomposition reactions have been shown to occur via the facile and reversible F/Ph rearrangement reaction of 1 to cis-[(Ph(3)P)(2)Rh(Ph)(Ph(2)PF)] (5), which has been isolated and fully characterized. Kinetic studies of the F/Ph rearrangement, an intramolecular process not influenced by extra phosphine, have led to the determination of E(a) = 22.7 +/- 1.2 kcal mol(-)(1), DeltaH(++) = 22.0 +/- 1.2 kcal mol(-)(1), and DeltaS(++) = -10.0 +/- 3.7 eu. Theoretical studies of F/Ph exchange with the [(PH(3))(2)(PH(2)Ph)RhF] model system pointed to two possible mechanisms: (i) Ph transfer to Rh followed by F transfer to P (formally oxidative addition followed by reductive elimination, pathway 1) and (ii) F transfer to produce a metallophosphorane with subsequent Ph transfer to Rh (pathway 2). Although pathway 1 cannot be ruled out completely, the metallophosphorane mechanism finds more support from both our own and previously reported observations. Possible involvement of metallophosphorane intermediates in various P-F, P-O, and P-C bond-forming reactions at a metal center is discussed.     

聚4-乙烯吡啶类高分子铑(I)化合物对甲醇羰化合成乙酸的催化性能

本文将聚4-乙烯吡啶(PVPy)、聚1-甲基-4-乙烯吡啶季铵碘(PVPyMe^+I^-)和4-乙烯吡啶/1-甲基-4-乙烯吡啶季铵碘共聚物[P(VPy-VPyMe^+I^-)]分别与四羰基二氯二铑反应制备成高分子铑(I)催化剂, 并考察了它们各自在甲醇羰化反应中的催化行为。结合IR光谱对这些催化剂结构的分析研究表明, 以上4-乙烯吡啶类高分子链上所含的功能基各自与铑(I)配合物离子之间以不同的链联方式所产生的不同结构的活性物种对催化反应性能有着显著的影响, 具有双配位的螯合型稳定结构的Rh(I)/PVPy催化剂, 表现出较差的催化反应活性, 而离子键合型的Rh(I)/PVPyMe^+I^-和杂键合型的Rh(I)/P(VPy-VPyMe^+I^-)催化剂均表现较佳的反应性能, 特别是Rh(I)/P(VPy-VPyMe^+I^-),由于其形成具有更强亲核性的五配位中间过渡态参与反应过程, 从而在较大程度上提高了催化反应速率。     

Transition metal-catalyzed dissociation of phosphine-gallane adducts: isolation of mechanistic model complexes and heterogeneous catalyst poisoning studies

Attempts to induce the catalytic dehydrocoupling of the phosphine-gallane adduct Cy2PH.GaH3 (Cy=cyclohexyl) (1) by treatment with ca. 5 mol% of either the Rh(I) complex [{Rh(mu-Cl)(1,5-cod)}2] (cod=cyclooctadiene) or the Rh(0) species Rh/Al2O3 and [Oct4N]Cl-stabilized colloidal Rh led to catalytic P-Ga bond cleavage to generate the phosphine, H2, and Ga metal. Interestingly, subsequent treatment of the reaction mixtures with Me2NH.BH3 failed to lead to the formation of [Me2N-BH2]2 via Rh-catalyzed dehydrocoupling, which suggested that catalyst deactivation was taking place. Poisoning studies involving the treatment of the active Rh(0) catalyst with Cy2PH, PMe3, or GaH3.OEt2 showed that deactivation indeed occurred as the dehydrocoupling of Me2NH.BH3 either dramatically decreased in rate or did not take place at all. The X-ray photoelectron spectroscopy analysis of colloidal Rh(0) that had been treated with Cy2PH and PMe3 confirmed the presence of phosphorus on the catalyst surface in each case, consistent with catalyst poisoning via phosphine ligation. A mechanism for the Rh-catalyzed P-Ga bond cleavage reaction of 1 and Me3P.GaH3 (2) is proposed and involves the initial reaction of Ga-H bonds with the Rh colloid surface, which weakens and ultimately breaks the P-Ga bond. The reasonable nature of this mechanism is supported by a model reaction between the zerovalent group 9 complex Co2(CO)8 and 2 which afforded Me3P.Ga[Co(CO)4]3 (3). Consistent with the elongated and thus weakened P-Ga bond in 3, solutions of this species in Et2O subsequently form the known complex [(Me3P)Co(CO)3]2 (4) and Ga metal after 4 h at 25 degrees C.     

Organophosphorus reagents as extractants-part 3. Synergic effect of triphenyl phosphine oxide and bis(diphenyl phosphinyl) alkanes on extraction of iron(III) from thiocyanate medium with 2,4-pentdione

The extraction of iron(III) from thiocyanate medium was carried out with a synergic combination of 2,4-pentdione (Hacac) and either triphenyl phosphine oxide (Ph(3) PO) or bis (diphenylphosphinyl) alkanes, Ph(2)P(O)(CH(2))(n).P(O)PH(2) [ligand abbreviation, n: dpeO(2), 2; dpbO(2), 4]. Iron(III) was quantitatively separated from its binary mixture with chromium(III), manganese(III), cobalt(II), nickel(II), zinc(II), cadmium(II), mercury(II), lead(II), magnesium(II) and from steel samples. Copper(II) and silver(I) however, interfered. The percentage extraction was 99.0%. The respective extraction constants, K(HA), K(L) or K(syn), for the extracted species, [Fe(NCS)(acac)(2)(H(2)O)] (HA Hacac), Fe(NCS)(3)L(2) [L b Ph(3)PO, dpeO(2) or dpbO(2)], or Fe(NCS)(acac)(2)L were found to be: K(HA), 1.48 x 10(3), K(L), 1.80 x 10(2) (L Ph(3)PO), 2.02 x 10(2) (L dpeO(2) or dpbO(2)) and K(syn), 1.87 x 10(6) (L Ph(3)PO), 2.56 x 10(6) [L dpeO(2) or dpbO(2)].     

Heterogeneous or homogeneous catalysis? Mechanistic studies of the rhodium-catalyzed dehydrocoupling of amine-borane and phosphine-borane adducts

In depth, comparative studies on the catalytic dehydrocoupling of the amine-borane adduct Me(2)NH.BH(3) (to form [Me(2)N-BH(2)](2)) and the phosphine-borane adduct Ph(2)PH.BH(3) (to form Ph(2)PH-BH(2)-PPh(2)-BH(3)) with a variety of Rh (pre)catalysts such as [[Rh(1,5-cod)(micro-Cl)](2)], Rh/Al(2)O(3), Rh(colloid)/[Oct(4)N]Cl, and [Rh(1,5-cod)(2)]OTf have been performed in order to determine whether the dehydrocoupling proceeds by a homogeneous or heterogeneous mechanism. The results obtained suggest that the catalytic dehydrocoupling of Me(2)NH.BH(3) is heterogeneous in nature involving Rh(0) colloids, while that of Ph(2)PH.BH(3) proceeds by a homogeneous mechanism even when starting with Rh(0) precursors such as Rh/Al(2)O(3). The catalytic dehydrocoupling reactions are thought to proceed by different mechanisms due to a combination of factors such as (i) the greater reducing strength of amine-borane adducts, (ii) the increased ease of dissociation of phosphine-borane adducts, and (iii) phosphine ligation and/or poisoning of active catalytic sites on metal colloids.     

通过"双离子键"固载于季鏻盐聚合物的[Rh(CO)I3]2–物种在多相乙醇羰基化中的应用

贵金属物种(Rh或Ir络合物)在均相羰基化和氢甲酰化催化过程得到了广泛的应用,但始终存在分离繁琐等问题,其均相多相化可很大程度上简化分离操作,故一直广受重视.单位点催化剂因其具有可与均相相比拟的较高金属利用率和选择性而成为均相多相化的重要研究方向之一.研究发现,在碘物种存在的情况下用于固载金属物种的配位键容易断裂,进而导致金属物种的流失,而通过离子键固载的[Rh(CO)₂I₂]^–物种更加稳定,比如著名的甲醇羰基化“Acetica^TM”工艺中,[Rh(CO)₂I₂]^–负一价阴离子物种是以离子键的方式固定在带有阳离子骨架的甲基化聚乙烯吡啶树脂上.与甲醇羰基化过程类似的乙醇羰基化过程是生产重要化工中间体丙酸的主要途径之一,但该过程的均相多相化始终存在着稳定性差这一关键问题.为了解决这一问题,基于之前将固载于季鏻盐聚合物的[Rh(CO)I₃]^2–应用于甲醇羰基化的工作,我们将类似的季鏻盐聚合物固载Rh基催化剂Rh-TPISP用于多相乙醇羰基化过程,通过多种表征进一步证明了Rh物种和P物种结构,并提出了“双离子键”模型.P的K边XANES证明了聚合物TPISP的季鏻化阳离子骨架特征.HAADF-STEM测试表明Rh-TPISP中的Rh呈现单位点分散的状态.Rh的XPS和XANES结果证明了Rh-TPISP中Rh物种的价态介于0~+1.通过EXAFS的拟合解析给出了[Rh(CO)I₃]^2–活性中心结构.由于[Rh(CO)₂I₂]^–为经典的羰基化活性中心,为了进一步证明该结构的正确性,我们将Rh-TPISP的EXAFS和IR谱图与标样[PPh3Et]⁺[Rh(CO)₂I₂]^–对比发现:在EXAFS谱图中,Rh-TPISP中的Rh-C峰高低于[PPh3Et]+[Rh(CO)₂I₂]^–的Rh-C峰高,而Rh-TPISP中的Rh-I峰高高于[PPh3Et]+[Rh(CO)₂I₂]^–的Rh-I峰高,这就说明Rh-TPISP中Rh物种的Rh-C配位数小于2,而Rh-I配位数大于2;在IR谱图中,标样[PPh3Et]+[Rh(CO)₂I₂]^–中有两个羰基振动峰,与该物种的两个Rh-C配位键相符,而Rh-TPISP中的只有一个羰基振动峰,说明Rh-C配位数为1.因此,Rh-TPISP催化剂的季鏻盐骨架中的每个P物种带有一个正电荷,每个带有两个负电荷的[Rh(CO)I₃]^2–通过与两个[P]⁺的静电作用进行固载,形成“双离子键”结构.该催化剂在固定床乙醇羰基化过程中表现出优异的羰基化活性、选择性和稳定性.在3.5 MPa、195 oC反应近1000 h后,Rh-TPISP催化剂TOF保持在约350 h–1,丙酰基选择性为95%以上,高出所有文献报道的均相和多相乙醇羰基化活性.其较高的活性主要是因为[Rh(CO)I₃]^2–比传统Rh活性相[Rh(CO)₂I₂]^–具有更强的富电子性,而较高的稳定性主要是由于“双离子键”这种强静电作用比“AceticaTM”工艺中“单离子键”更有利于Rh物种的固载.故Rh-TPISP催化剂中的“双离子键”对其优异的催化性能具有极其重要的作用,对后续多相乙醇羰基化的发展具有重要意义.     

Selective homo- and heterodehydrocouplings of phosphines catalyzed by rhodium phosphido complexes

Reactions of the rhodium complex (dippe)Rh(eta3-CH2Ph) (1, dippe = iPr2PCH2CH2PiPr2) with ArPH2 (Ar = Ph, Mes) proceed via P-H oxidative additions to the phosphido complexes (dippe)Rh(mu-PHAr)2Rh(dippe) (3a, Ar = Ph; 3b, Ar = Mes). The corresponding reaction of Ph2PH occurs similarly, via the intermediate (dippe)Rh(PPh2)PHPh2 (4), to (dippe)Rh(mu-PPh2)2Rh(dippe) (3c). Complexes 3a-c and 4 are catalysts for the catalytic dehydrodimerizations of the corresponding phosphines to diphosphanes. Complex 1 is a more active dehydrocoupling catalyst, and substituent effects suggest that the active catalyst is mononuclear. Efficient dehydrocouplings of 2-EtC6H4PH2, 2-iPrC6H4PH2, and 2,4,6-iPr3C6H2PH2 were also observed. Complex 1 also catalyzes the heterocoupling of Ph2PH with PhSH (to Ph2P-SPh), and stoichiometric reactions in this system allowed isolation of (dippe)Rh(mu-SPh)2Rh(dippe) (6) and (dippe)Rh(SPh)PHR2 (7a, R2PH = MesPH2; 7b, R2PH = Ph2PH).