The dimerisation of monosubstituted α-hydroxyacetylenes by use of tris(triphenylphosphine)chlororhodium(<scp>I</scp>) as catalyst

Singer, Hellmut; Wilkinson, Geoffrey

doi:10.1039/j19680000849

Cited by 71 publications

(27 citation statements)

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“…This linear correlation between vco and o,,provides additional support for Singer and Wilk~nson's claim that the stereochemistry of the oxidative addition product is that shown in Fig. 2 which would result from cis-addition (3). It may also be concluded that this stereochemistry is comlnon to all the benzenethiolo adducts reported here by virtue of the fact that the high-field chemical shift of the hydrogen bonded to iridium is invariant to the nature of the para-substituent.…”

Section: Resultssupporting

confidence: 58%

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Oxidative addition of substituted benzenethiols to trans-chlorocarbonylbis(triphenyl phosphine)iridium(I)

Senoff¹

1970

Can. J. Chem.

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A series of para-substituted benzenethiols have been shown to react with lrnr~s-IrC1(CO)(Ph3P)2, to form IrHCI(SC6H4Y)(CO)(P1~,P), where Y = NO,, Br, C1, F, H, CH,, and CH3O. A good correlation between the vco vibration in the infrared spectra of these complexes and the Hammett substituent parameter, o,, was observed indicating that the vm vibration may be used to provide a measure of the transmission of the para-substituent's electronic effect to the central iridium atom.

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Section: Resultssupporting

confidence: 58%

“…As part of a study of the photochemistry of P-substituted o-divinylbenzenes (l), we have uncovered yet another example of a phosphorane-ester carbonyl condensation (2)(3)(4).…”

mentioning

confidence: 99%

Oxidative addition of substituted benzenethiols to trans-chlorocarbonylbis(triphenyl phosphine)iridium(I)

Senoff¹

1970

Can. J. Chem.

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“…9 Specifically, 2-methylbut-3-yn-2-ol ( 1 ) was smoothly converted to ( E )-head-to-head product 2 in 73% yield by the action of RhCl(PPh 3 ) 3 in refluxing benzene (Scheme 3). 1-Ethynylcyclohexanol was similarly dimerized in high yield, but the reaction of an aryl alkyne afforded a complex product mixture.…”

Section: Rhodium Catalysismentioning

confidence: 99%

Transition metal-catalyzed couplings of alkynes to 1,3-enynes: modern methods and synthetic applications

2016

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The metal-catalyzed coupling of alkynes is a powerful method for the preparation of 1,3-enynes, compounds that are of broad interest in organic synthesis. Numerous strategies have been developed for the homo- and cross coupling of alkynes to enynes via transition metal catalysis. In such reactions, a major issue is the control of regio-, stereo-, and, where applicable, chemoselectivity. Herein, we highlight prominent methods for the selective synthesis of these valuable compounds. Further, we illustrate the utility of these processes through specific examples of their application in carbocycle, heterocycle, and natural product syntheses.

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“…Another possible pathway for the dimerization is an intermolecular, nonoxidative coupling between two ethynyl groups, promoted by rhodium complex VI , generating in this case enyne 11 (Scheme ). Dimerizations of this type involving terminal alkynes have been reported in the presence of Wilkinson's catalyst 43–45. Single‐bridged enyne 11 may well participate in further reactions yielding products similar to those described for the oxidative route [double‐bridge formation ( 12 ), oligomerization, and polymerization].…”

Section: Resultsmentioning

confidence: 95%

Synthesis and Rh(I)‐catalyzed polymerization of 1,3‐diphenylyne–calix[4]arene compounds: Novel conjugated, calixarene‐based polymers

Costa

Prata

2006

J. Polym. Sci. A Polym. Chem.

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The synthesis of two 1,3‐bis(4‐ethynylbenzyloxy)calix[4]arenes, 5,11,17,23‐tetrakis(1,1‐dimethylethyl)‐25,27‐bis(4‐ethynylbenzyloxy)‐26,28‐dihydroxycalix[4]arene (1) and 25,27‐bis(4‐ethynylbenzyloxy)‐26,28‐dihydroxycalix[4]arene (2), was accomplished through Sonogashira coupling of appropriate calixarene derivatives. Methods for the polymerization of these bifunctional building blocks with Rh(I) as a catalyst, leading ultimately to conjugated polymers having calix[4]arene units incorporated into the main chain, were explored. Calixarenes 1 and 2 were efficiently polymerized with rhodium‐based initiators and afforded the conjugated polymers poly{5,11,17,23‐tetrakis(1,1‐dimethylethyl)‐25,27‐bis(4‐ethynylbenzyloxy)‐26,28‐dihydroxycalix[4]arene} (poly 1) and poly{25,27‐bis(4‐ethynylbenzyloxy)‐26,28‐dihydroxycalix[4]arene}. Depending on the conditions, high conversions and good yields were obtained. The effects of adding cocatalysts (NHEt2 and/or PPh3) were studied in connection with the number‐average molecular weight and the molecular weight distribution of the resultant polymer (poly 1) and tentatively correlated with the formation of low‐molecular‐weight materials. A catalytic system containing triphenylphosphine as the sole additive ([Rh(nbd)Cl]2; [Rh]/[PPh3] = 0.5) proved to be the best for the polymerization of p‐tert‐butylcalixarene compound 1. Linear polymers having high number‐average molecular weights (up to 1.1 × 105 g mol−1) with low polydispersities were produced under these conditions. For debutylated homologue 2, its polymerization was best carried out in the absence of any added cocatalyst. A cyclopolymerization route, comprising the intramolecular ring closing of the calix[4]arene pendant ethynyl groups followed by an intermolecular propagation step, is advanced to explain the results. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 7054–7070, 2006

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The dimerisation of monosubstituted α-hydroxyacetylenes by use of tris(triphenylphosphine)chlororhodium(I) as catalyst

Abstract: No reprints available.

Cited by 71 publications

References 0 publications

Oxidative addition of substituted benzenethiols to trans-chlorocarbonylbis(triphenyl phosphine)iridium(I)

Oxidative addition of substituted benzenethiols to trans-chlorocarbonylbis(triphenyl phosphine)iridium(I)

Transition metal-catalyzed couplings of alkynes to 1,3-enynes: modern methods and synthetic applications

Synthesis and Rh(I)‐catalyzed polymerization of 1,3‐diphenylyne–calix[4]arene compounds: Novel conjugated, calixarene‐based polymers

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