Oxidation of the α-tocopherol model compound 2,2,5,7,8-pentamethyl-6-chromanol in the presence of alcohols

Oxidation of the vitamin E model compound, 2,2,5,7,8-pentamethyl-6-chromanol (1b) byt-butyl hydroperoxide in chloroform has been studied in the presence of ethanol, heptanol and cholesterol. In the absence of an alcohol, the major products were the spirodimer (13b) and spirotrimer (14b) of 1b, together with 1H,2,3-dihydro-3,3,5,6,9,10,11a(R)-heptamethyl-7a(S)-(3-hydroxy-3-methylbutyl)-pyrano[2,3-a] xanthene 8(7aH), 11(11aH) dione (6b). In the presence of ethanol, heptanol and cholesterol, the major products were 5-ethoxymethyl-2,2,7,8-tetramethyl-6-chromanol (16b), 5-heptoxymethyl-2,2,7,8-tetramethyl-6-chromanol (17) and 5-cholesteroxymethyl-2,2,7,8-tetramethyl-6-chromanol (18). However, when water was present in a homogeneous reaction, the most rapidly formed product was 2-(3-hydroxy-3-methylbutyl)-3,5,6-trimethyl-1,4-benzoquinone (5b). Compounds 13b, 14b, 16b, 17 and 18 are formedvia a quinone methide intermediate, and compound 5b is formedvia a phenoxylium ion. The phenoxylium species appears to be the preferred intermediate when water is present, whereas the quinone methide species is prefered in the absence of water.     

Effect of alcohols on the oxidation of the vitamin E model compound, 2,2,5,7,8-pentamethyl-6-chromanol

The vitamin E model compound, 2,2,5,7,8-pentamethyl-6-chromanol, has been oxidized witht-butyl hydroperoxide in chloroform in order to simulate in vivo oxidations due to lipid hydroperoxides. In the presence of a variety of alcohols, ranging from methanol to cholesterol, the corresponding 5-alkoxymethyl-2,2,7,8-tetramethyl-6-chromanols were formed in fair to good yield and were the major products in each reaction.     

Antioxidant activity of oxidation products of α-tocopherol and of its model compound 2,2,5,7,8-pentamethyl-6-chromanol

A variety of oxidation products (4–29) of α-tocopherol, 1 and of its model compound, 2,2,5,7,8-pentamethyl-6-chromanol (2) has been tested for antioxidant activity against autoxidizing safflower oil (ASO) and autoxidizing methyl linoleate (AML). The following compounds showed good antioxidant activity against both substrates: 5-hydroxymethyl-2,2,7,8-tetramethyl-6-chromanol (4), 5-(2,2,5,7,8-pentamethyl-6-chromanoxy)methyl-2,2,7,8-tetramethyl-6-chromanol (15), 1,2-bis(2,2,7,8-tetramethyl-6-chromanol-5-)ethane (16), 5-ethoxymethyl-7,8-dimethyltocol (19), 5-mthoxymethyl-2,2,7,8-tetramethyl-6-chromanol (21), 5-ethoxymethyl-2,2,7,8-tetramethyl-6-chromanol (20), 5-propoxymethyl-2,2,7,8-tetramethyl-6-chromanol (22), 5-butoxymethyl-2,2,7,8-tetramethyl-6-chromanol (23), 5-(2-methyl-1-propoxy)methyl-2,2,7,8-tetramethyl-6-chromanol (24), 5-(2-methyl-2-propoxy)methyl-2,2,7,8-tetramethyl-6-chromanol (25), 5-heptoxymethyl-2,2,7,8-tetramethyl-6-chromanol (26), 5-undecoxymethyl-2,2,7,8-tetramethyl-6-chromanol (27), 5-phytoxymethyl-2,2,7,8-tetramethyl-6-chromanol (28) and 5-cholesteroxymethyl-2,2,7,8-tetramethyl-6-chromanol (29). 2,2,7,8-Tetramethylchroman-5,6-dione (17) and 1,2-bis(2,2,7-trimethylchroman-5,6-dione-8-)ethane (18) showed significant antioxidant activity against ASO but not against AML. If the corresponding oxidation products of 1 are formedin vivo it means that the antioxidant activity of 1 is not lost on oxidation. This may help to explain the outstanding capacity of 1 to protect cell membranes.     

Oxidations of the α-tocopherol model compound 2,2,5,7,8-pentamethyl-6-chromanol. Formation of 2,2,7,8-tetramethylchroman-5,6-dione

Overoxidation of α-tocopherol (1a) by silver nitrate produces tocored (9a) as a major product. The aim of the present work was to elucidate the pathway of formation of tocored using the α-tocopherol model compound, 2,2,5,7,8-pentamethyl-6-chromanol (1b). Oxidation of 1b by silver nitrate in ethanol produces 2-(3-hydroxy-3-methylbutyl)-3,5,6-trimethyl-1,4-benzoquinone (6b) and 2,2,7,8-tetramethylchroman-5,6-dione (9b, the model compound of tocored) as major products. Formation of 6b is rapid and is accompanied by an equally rapid fall in pH. Formation of 9b only occurs after 6b has reached maximum concentration and has begun to decline. It appears that acid promotes the dehydration and recyclization of 6b into a quinone methide (2b), which is then rehydrated into 5-hydroxymethyl-2,2,7,8-tetramethyl-6-chromanol (5b), the phenolic isomer of the quinone 6b. Oxidative deformylation of 5b leads to 9b. It is also demonstrated that 6b, heated in ethanol in the presence of acid and in the absence of any oxidizing agent, is converted into 9b, 1b, 5-ethoxymethyl-2,2,7,8-tetramethyl-6-chromanol (4b) and 2-(3-hydroxy-3-methylbutyl)-3-ethoxymethyl-5,6-dimethyl-1,4-benzoquinone (7b). It seems that dehydration and recyclization of 6b into 5b occurs as above and that 6b then oxidizes 5b into 9b, while being reduced into the hydroquinone of 6b (6bH₂). Compound 6bH₂ then cyclizes in acid to 1b. A possible alternative pathway from 6b to 9b that does not involve 5b is also discussed. These results suggest that 6b and, by implication, α-tocopheryl quinone (6a), is not a stable compound and, in the presence of acid, is readily oxidized to 9b.     

Further oxidation products of 2,2,5,7,8-pentamethyl-6-chromanol

In order to undertake a quantitative study by high-performance liquid chromatography of the rate of oxidation of 2,2,5,7,8-pentamethyl-6-chromanol (1), the model compound of α-tocopherol, a number of potential products were required as standards. Among these compounds were 2,2,7,8-tetramethylchroman-5,6-dione (10) and 2,2,7-trimethyl-6-hydroxychroman-5,8-dione (17), the model compounds of tocored and tocopurple, respectively. Attempts to synthesize 10 and 17 led to the isolation of 8-hydroxymethyl-2,2,7-trimethylchroman-5,6-dione (14) and 1,2-bis(2,2,7-trimethylchroman-5,6-dione-8-)ethane (19) a dimer of 10. Purification by thin-layer chromatography of the spirodimer (20) of 1 resulted in an acid-catalyzed decomposition to 1-(2,2,7,8-tetramethyl-6-chromanol-5-)2-[2-(3-methyl-3-hydroxybutyl)-5,6-dimethyl-1,4-benzoquinone-3-]ethane (23), a new chromanol-quinone dimer.     

Reaction products of tocopherols

Tocopherols readily undergo oxidation with a variety of oxidizing agents. Considerable effort has gone into isolation and identification of these various oxidation products. In many cases they can undergo further transformations upon treatment with various chemical reagents. This review will focus on the oxidation of α-tocopherol and transformation of its oxidation products to new derivatives. Dimeric and trimeric oxidation products will not be covered. Early work on the oxidation of α-tocopherol led to identification of α-tocopherol quinone as an oxidation product formed by FeCl₃ oxidation. Stronger oxidizing conditions with FeCl₃ or oxidation with AgNO₃ or HNO₃ led to the orthoquinone and the hydroxy-p-quinone due to loss of one or two methyl groups from the aromatic ring. These early studies pointed out the unusual reactivity of the 5-methyl group of α-tocopherol. Oxidation of α-tocopherol with benzoyl peroxide led to substitution of a benzoate on the 5-methyl group. A similar reaction occurs when diasobisisobutyronitrile is used as the oxidizing agent. The oxidation of α-tocopherol by tetrachloro-o-quinone in aqueous acetonitrile resulted in the formation of 9-hydroxy-α-tocopherone. When FeCl₃ was used as the oxidizing agent in the presence of α,α'-bibyridyl in ethanol, 9-ethoxy-α-tocopherone was formed. α-Tocopherolquinone can be reduced with Zn−HOAc or by catalytic hydrogenation to the hydroquinone or reductively cyclized to α-tocopherol with Zn−HBr. Reaction of α-tocopherolquinone with acetyl chloride resulted in the 5-chloromethyl-6-acetoxy derivative which has been converted to a variety of 5-methylsubstituted derivatives. Reaction of α-tocopherol with Br₂ led to the 5-bromomethyl derivative. When α-tocopherolquinone was treated with hydrochloric, phosphoric, citric or tartaric acid, in the absence of oxygen, a disproportionation took place forming α-tocopherol, α-tocored and other oxidation products. An interesting isomerization of α-tocored, the orthoquinone, occurs in the presence of aqueous HCl to yield the yellowp-quinone with the chroman ring closed. The 5-benzoyloxymethyl derivative upon treatment with HCl generateso-quinone methide which can be trapped by reaction with tetracyanoethylene or dihydropyran. Treatment of the 5-benzoyloxmethyl derivative with HCl in ethanol followed by sublimation yielded the 5-aldehyde of α-tocopherol. Recently, a series of phosphate derivatives of α-tocopherol or its model, 2,2,5,7,8-pentamethyl-6-chromanol, were synthesized. Tris (6-acetoxy-5-methyleneoxy-7,8-dimethyltocol)phosphate, tris(2,2,5,7,8-pentamethyl-6-chromanol)phosphate, 5-hydroxymethyl-2,2,7,8-tetramethyl-6-chromanol phosphate and the cyclic 5-methylenoxy-2,2,7,8-tetramethyl-6-chromanol phosphate, were prepared. These phosphates are of interest in view of a possible role of α-tocopherol in oxidative phosphorylation. One of six papers to be published from the Symposium “Chemistry and Biochemistry of Tocopherols” presented at the ISF-AOCS World Congress, Chicago, September 1970.     

Radical addition of linoleic hydroperoxides to α-tocopherol or the analogous hydroxychroman

Either linoleic acid hydroperoxide (LOOH) or methyl linoleate hydroperoxide react anaerobically with either α-tocopherol (TOH) or its model compound-2,2,5,7,8-pentamethyl-6-hydroxychroman (COH)-to form principally an addition compound of the two reactants. The reaction can be catalyzed either by 1.28 X 10⁻⁵ M Fe(III) or by proflavin (0.01%) sensitized by visible light. The presence of air in the reaction terminates the addition, and quinones become the major products from TOH or its model compound. The addition compound synthesized from COH and LOOH (a 4.9∶1 ratio of 13-hydroperoxy-cis-9,trans-12-octadecadienoic acid and 9-hydroperoxy-trans-10,cis-12-octadecadienoic acid) was used to solve structural details of the bridging function. Three isomers of the addition compound (methyl esterified) were isolated and identified as methyl 11-(2,2,5,7,8-pentamethyl-6-oxychroman)-cis-12,13-epoxy-trans-9-octadecenoate; methyl 11-(2,2,5,7,8-pentamethyl-6-oxychroman)-trans-12,13-epoxy-trans-9-octadecenoate; and methyl 11-(2,2,5,7,8-pentamethyl-6-oxychroman)-cis-9,10-epoxy-trans-12-octadecenoate in order of decreasing abundance. The mechanism appears to be free radical addition brought about by the catalytic formation of alkoxy radicals from the hydroperoxide and chromanoxy radicals from TOH or its model. Presented at the AOCS Meeting, Atlantic City, N.J. October 1971. N. Market. Nutr. Res. Div., ARS, USDA.     

New oxidation products of α-tocopherol

A major product of the reaction between α-tocopherol andt-butyl hydroperoxide in chloroform is 5-ethoxymethyl-7,8-dimethyl tocol, the source of the ethoxy group being the ethanol that is used to stabilize the chloroform. Two new products of this oxidation have now been identified as 2-(3′-hydroxy-3′,7′,11′,15′-tetramethylhexadecyl), 3-ethoxymethyl-5,6-dimethylbenzo-1,4-quinone and 5-ethoxycarbonyl-7,8-dimethyl tocol. These two compounds and another major product, 5-formyl-7,8-dimethyl tocol appear to be formed by further oxidation of 5-ethoxymethyl-7,8-dimethyl tocol.     

Synthesis of 3-alkylated triacetonamine derivatives

Reaction of a lithiated imine derivative of 2,2,6,6-tetramethyl-4-piperidone (triacetonamine, 1 ) with activated or less reactive alkyl halides or styrene oxide and subsequent hydrolysis afforded 3-alkylated triacetonamine derivatives. Thus, 3-benzyl-2,2,6,6-tetramethyl-4-piperidone ( 3 ), 3-(n-butyl)-2,2,6,6-tetramethyl-4-piperidone ( 4 ), 3-(3-chloropropyl)-2,2,6,6-tetramethyl-4-piperidone ( 5 ), 2,2,3,6,6-pentamethyl-4-piperidone ( 6 ) and two diastereomers of 3-(2-hydroxy-2-phenylethyl)-2,2,6,6-tetramethyl-4-piperidone ( 7 ) were prepared in 26–53% yield. Reaction of the imine anion derived from 1 with benzyl bromide to give 3 has to be performed at low temperatures in order to avoid a competing proton transfer. No reaction at the unprotected piperidine nitrogen was observed.     

Synthesis of a phosphatidyl derivative of vitamin E and its antioxidant activity in phospholipid bilayers

A novel phospholipid containing a chromanol structure at its polar head group was synthesized from egg yolk phosphatidylcholine and 2,5,7,8-tetramethyl-6-hydroxy-2-(hydroxyethyl)chroman by transphosphatidylation catalyzed by phospholipase D fromStreptomyces lydicus. The structure of the product synthesized was shown by spectral analysis to be 1,2-diacyl-sn-glycero-3-phospho-2′-hydroxyethyl-2′ 5′,7′,8′-tetramethyl-6′-hydroxychroman. The phosphatidylchromanol (PCh) showed antioxidant activity against radical chain oxidation of methyl linoleate in solution in a manner similar to that ofd-α-tocopherol (α-Toc) and 2,2,5,7,8-pentamethyl-6-chromanol. However, PCh was less effective as a chain-breaking antioxidant than was α-Toc when unilamellar egg yolk phosphatidylcholine liposomes were exposed to either a water-soluble or a lipid-soluble radical initiator. It is likely that the phospholipid nature of PCh affects the location and the mobility of the chromanol moiety in the membrane bilayer resulting in a decrease in antioxidant activity. On the other hand, the antioxidant activity of PCh was little different from that of α-Toc in unilamellar liposomes when exposed to a lipid-soluble radical initiator in the presence of ascorbic acid. It appears that PCh in phospholipid bilayers can be regenerated by ascorbic acid in aqueous phase as can be α-Toc. The new phospholipid, phosphatidylchromanol, should prove useful as a chain-breaking antioxidant in phospholipid membranes.     

Mechanism of lower oxidizability of eicosapentaenoate than linoleate in aqueous micelles. II. Effect of antioxidants

We have reported that the peroxyl radicals derived from methyl eicosapentaenoate (20:5n-3) are more polar than those from methyl linoleate (18:2n-6) since the former peroxyl radicals have at least two molecules of oxygen in a molecule while the latter peroxyl radical has one. This lowers the oxidizability for 20:5n-3 in aqueous Triton X-100 micelles by enhancing the termination reaction rate for peroxyl radicals and by reducing the rate of propagation since there may be more polar peroxyl radicals derived from 20:5n-3 at the surface than within the micelle core. In this study, we measured the effect of three antioxidants, di-tert-butyl-4-methylphenol (BHT), 2,2,5,7,8-pentamethyl-6-chromanol (PMC) and 2-carboxy-2,5,7,8-tetramethyl-6-chromanol (Trolox), on the oxidation of lipids in aqueous micelle. Antioxidants give a clear induction period during oxidation of 18:2n-6 initiated with a water-soluble radical initiator, and its induction length decreases in the order of BHT>PMC>Trolox. This is consistent with the proposed location of three antioxidants: being in the core of micelle, at the surface, or in aqueous phase, respectively. However, BHT does not inhibit the oxidation of 20:5n-3 efficiently, and its rate of oxidation is slower than that observed in the oxidation of 18:2n-6, supporting the idea that polar peroxyl radicals derived from 20:5n-3 are preferentially located at the surface of the micelle. Similar results were obtained when oxidation was initiated with a lipid-soluble radical initiator except antioxidants had lesser effect on the oxidation rate of 20:5n-3.     

Sensitized photooxidation of α-tocopherol and of 2,2,5,7,8-pentamethyl-6-chromanol in ethyl acetate

The major product of each photo-oxidation was an equimolar mixture of quinone oxide and quinone. The yield of this mixture was 64% and 67% when the substrate was α-tocopherol and 2,2,5,7,8-pentamethyl-6-chromanol, respectively. Neither spirodienone dimer nor trimer was present in the product mixture. Evidently the reaction intermediate is an adduct of tocopherol and singlet oxygen. Tocopherol may protect biological lipids from singlet oxygen degradation. ²N. Market. Nutr. Res. Div., ARS, USDA.     

Epoxidation of methallyl chloride with t-butyl hydroperoxide

By applying a statistical method of experiment planning the optimum conditions of methallyl chloride epoxidation with t-butyl hydroperoxide have been determined. The influences of the temperature, molar ratio of the methallyl chloride to t-butyl hydroperoxide, catalyst concentration and reaction time on the selectivity of the synthesis of methylglycerol epichlorohydrine in relation to reacted t-butyl hydroperoxide have been examined.     

Model Study of Different Antioxidant Properties of α- and γ-Tocopherol in Fats

A model study using 2,2,5,7,8-pentamethyl-6-hydroxychroman (α-COH) and 2,2,7,8-tetramethyl-6-hydroxychroman (γ-COH) as antioxidants, and linoleic acid and its methyl ester (both in bulk phase) as the lipids was performed. After having demonstrated that the antioxidative activities of the model substances did agree with those of the corresponding tocopherols (α-T, γ-T), the stability of α-COH and γ-COH was determined, and the products arising from α-COH, γ-COH, linoleic acid and its methyl ester were identified. α-COH did oxidize to different major products (quinone, trimer) depending on the reaction temperature (37°C and 47°C) and the antioxidant concentration, whereas the products obtained by oxidation of γ-COH (diphenyl ether dimer, biphenyl dimer) did not seem to be affected by differences in the reaction conditions. It was concluded that γ-T was superior to α-T as antioxidant because it appears more stable and, also, being oxidized to compounds which are still effective as antioxidants.     

Protective effect of a vitamin E analog, phosphatidylchromanol, against oxidative hemolysis of human erythrocytes

The protective effect of a vitamin E analog, phosphatidylchromanol [1,2-diacyl-sn-glycero-3-phospho-2′-(hydroxyethyl)-2′, 5′,7′,8′-tetramethyl-6′-hydroxychroman; PCh], against oxidative hemolysis of human erythrocytes was examined and was compared with those of vitamin E (α-tocopherol) and 2,2,5,7,8-pentamethyl-6-chromanol (PMC). These three compounds at 50 μM protected the erythrocytes from hemolysis, when erythrocyte suspension (10%, vol/vol) was incubated with a water-soluble radical generator, 2,2′-azobis(2-amidino-propane)-dihydrochloride (75 mM). When erythrocyte suspension was oxidized after pretreatment with these compounds (50 μM) for 30 min followed by washing, PCh protected about 54% of erythrocytes from the hemolysis, while α-tocopherol protected only about 16% of the cells and PMC did not show any protective effect. During preincubation, α-tocopherol, PMC, and PCh were incorporated into the cells at the concentration of 12.6, 3.7, and 16.3 nmol/mg protein, respectively. Moreover, PCh was found in the ghost membrane fraction at a 20% higher level than α-tocopherol, and no PMC was detected in this fraction. These results indicate that phosphatidyl group in PCh accts as an excellent carrier of chromanol moiety into cells as well as an anchor within membranes more efficiently than phytyl group in α-tocopherol. PMC seems to be slightly anchored within membranes because of the lack of hydrophobic side chain. The excellent antihemolytic activity of PCh is likely to be caused by its accumulation within erythrocyte membranes.     

Optimizing reaction parameters for the enzymatic synthesis of epoxidized oleic acid with oat seed peroxygenase

Peroxygenase is a plant enzyme that catalyzes the oxidation of a double bond to an epoxide in a stereospecific and enantiofacially selective manner. A microsomal fraction containing peroxygenase was prepared from oat (Avena sativa) seeds and the enzyme immobilized onto a hydrophobic membrane. The enzymatic activity of the immobilized preparation was assayed in 1 h by measuring epoxidation of sodium oleate (5 mg) in buffer-surfactant mixtures. The pH optimum of the reaction was 7.5 when t-butyl hydroperoxide was the oxidant and 5.5 when hydrogen peroxide was the oxidant. With t-butyl hydroperoxide as oxidant the immobilized enzyme showed increasing activity to 65°C. The temperature profile with hydrogen peroxide was flatter, although activity was also retained to 65°C. In 1 h reactions at 25°C at their respective optimal pH values, t-butyl hydroperoxide and hydrogen peroxide promoted epoxide formation at the same rate. Larger-scale reactions were conducted using a 20-fold increase in sodium oleate (to 100 mg). Reaction time was lengthened to 24 h. At optimized levels of t-butyl hydroperoxide 80% conversion to epoxide was achieved. With hydrogen peroxide only a 33% yield of epoxide was obtained, which indicates that hydrogen peroxide may deactivate peroxygenase.     

Reaction of 5-Amino-2,3-dicyano-1,4-naphthoquinone with Arylamines

The reaction of 5-amino-2,3-dicyano-1,4-naphthoquinone (1) with arylamines gave 5-amino-8-arylamino- (2), 5,8-bis(arylamino)- (3), and 5-hydroxy-8-arylamino-2,3-dicyano-1,4-naphthoquinone (4) together with 5-amino-2-arylamino-3-cyano- (5) and 5-amino-2-cyano-3-aryl-amino-1,4-naphthoquinone (6). It is proposed that the initial quinone-quinoneimine tautomerism of 1 to 4-hydroxy-2,3-dicyano-5-imino-1,5-naphthoquinone 7 facilitates the 8-arylamination. Some derivatives of 2 have good properties as dyes for optical information-recording media for semiconductor lasers.     

Epoxidation of chloromethylbutenes by t-butyl hydroperoxide

The epoxidation of chloromethylbutenes by t-butyl hydroperoxide in the presence of Mo(CO)₆ has been investigated. The influence of important parameters on hydroperoxide conversion, selectivity of transformation to epoxy compound in relation to hydroperoxide used, yield in relation to olefin introduced (response function) has been described by regression equations in the form of a second order polynomial. The optimum values of: temperature, olefin to hydroperoxide molar ratio, reaction time, molar ratio of Mo(CO)₆ catalyst to hydroperoxide, ensuring the maximum values of these functions, have been determined. ©1997 SCI     

The effect of a partly hydrolyzed styrene-tert-butyl acrylate diblock copolymer on the properties of poly(2,6-dimethyl-1,4-phenylene ether) (PPE) and polyamide-6 (PA) blends

The compatibilizing effect of a polystyrene-hydrolyzed poly(t-butyl acrylate) diblock copolymer (SBAH) on the phase structure, rheological properties, and mechanical properties of immiscible poly(2,6-dimethyl-1,4-phenylene ether) (PPE) and polyamide-6 (PA) blends was investigated. The SBAH was prepared by sequential anionic polymerization of styrene and t-butyl acrylate, followed by acid-catalyzed hydrolysis of t-butyl acrylate block. Scanning electron micrographs show that the blends exhibit a more regular and finer dispersion when the SBAH of 47% hydrolyzed t-butyl acrylate block is added. By addition of small amount of the block copolymer, the blends show non-Newtonian power-law behavior, and the contribution of storage modulus (G′) to the total response increases. Solubility tests support the formation of graft copolymer by chemical reaction between amine groups of the PA and carboxyl groups of the SBAH. Both modulus and strength are improved about 20% with addition of the 3 wt% SBAH, while the elongation at break decreases notably; thus, the blends fail in a brittle manner.     

Synthesis and properties of polyacetylenes containing carbazolylmethyl groups

Novel acetylene monomers containing carbazolymethyl groups, 3,5-bis[(3,6-di-t-butyl)carbazolylmethyl]-1-ethynylbenzene (1), 3-(3,6-di-t-butyl)carbazolylmethyl-1-ethynylbenzene (2), and 4-(3,6-di-t-butyl)carbazolylmethyl-1-ethynylbenzene (3) were synthesized, and polymerized with [(nbd)RhCl]₂-Et₃N, Rh⁺(nbd)[η⁶-C₆H₅B⁻(C₆H₅)₃], and WCl₆-n-Bu₄Sn catalysts. The corresponding polyacetylenes with number-average molecular weights ranging from 1600 to 115,000 were obtained in 18%-quantitative yields. The UV-vis absorption band edge wavelengths of the polymers obtained with W catalyst were longer than those of the Rh-based polymers. The photoluminescence quantum yields of the W-based polymers were 1.1-3.1%, while those of the Rh-based ones were 0.18-4.1%.