Thienyl iodide

Similar coupling and iodination reactions are observed with thienyl iodide, as shown in Eq. 2.38 [35]. Thus, carbon—carbon bond formation occurs with the first molecule of thienyl iodide, and subsequent Cu/I exchange occurs with the second molecule. 

Eq. 2.38. Coupling reaction of a zirconacyclopentadiene with thienyl iodide. 

Telluronium Dimethyl- 3-[l-(l,3-dioxolan-2-yl)-ethyl]-2-thienyl-(Iodide) El2b, 680 (Ar-TeLi + HSC-I)... 

Electron-donating and electron-withdrawing substituents on the aryl iodide 6 are equally well tolerated, while heteroaryl iodides are generally not tolerated except for 1-thienyl iodide. In comparison to the weU-desciibed alkynone approach towards pyrazoles with acid chlorides as starting materials, this sequence allows the introduction of unprotected phenol groups. 

Pd-catalyzed cyanocarbonylation of aryl iodides with potassium cyanide is effected by 1% of PdPdI(PPh3)2 under 20 atm of CO at 100 °C (Scheme 40). The optimum ratio of KCN to Arl differs from aryl iodide to aryl iodide, and the best yield of aroyl cyanides is usually obtained with 0.5-0.3 equiv of KCN. The direct coupling product (arylcyanide) is produced in negligibly small amount (< 2%) except for the reaction of 2-thienyl iodide, which furnishes a mixture of cyano 2-thienyl ketone (45%) and 2-cyanothiophene (22%, under 8 atm CO, 100 °C, 24 h). Aryl bromides do not work well. 

The 3- and4-arylfuran-2(5//)-ones 152 and 153 (Ar = Ph, 2-Me—COO—QH4, 3-CF3—C6H4, 2-Me—C6H4, 2-thienyl) were conveniently obtained by coupling of 3- and4-stannylfuranones 151 and 134 with aryl iodides using dichloro-bis(triphe-nylphosphine)Pd(II) as catalyst and toluene as the solvent [96JCS(P1)1913]. 

Recently, the required heteroaromatic organozinc halides for the Negishi reaction have also been prepared using microwave irradiation [23]. Suna reported that a Zn - Cu couple (activated Zn), prepared using a slightly modified LeGoff procedure from Zn dust and cupric acetate monohydrate, allowed the smooth preparation of (3-pyridinyl)zinc iodide and (2-thienyl)zinc iodide... 

S-methyl-N-(2-chloro-4- methyl 3 - thienyl) -Isothiouronium iodide (1)... 

CN 4-[3-hydroxy-3-phenyl-3-(2-thienyl)propyl]-4-methyImorphoIinium iodide... 

The protonation of 185 and 186 with trifluoroacetic acid (TFA) gave 4-(/i t/-butylthio)-3,6-diphenyl- 193 and 4-(ter1-butylthio)-3,6-di(2-thienyl)thieno[3,4-f]thiophene-l(3//)-thione 194 (Scheme 18). The treatment of 193 with sodium hydride and then isopropyl iodide led to 4-(/i< t/-butylthio)-3,6-diphenyl-l-(isopropylthio)thieno[3,4-f]thio-phene 195 by the regeneration of the thieno[3,4-f]thiophene ring system, thus making possible the synthesis of other alkylthio-substituted thieno[3,4-(r]thiophene derivatives. When the reaction of 185 with TFA was carried out... 

Another total synthesis of sufentanil has been described the cyclization of 2-(2-thienyl)ethylamine with allyl-trimethylsilane and formaldehyde gives 4-hydroxy-1-[2-(2-thienyl)ethyl]piperidine, which is oxidized with oxalyl chloride in DMSO/dichloromethane to 1-[2-(2-thienyl) ethyl]piperidin-4-one. The epoxidation of this compound by means of trimethylsulfonium iodide and the sodium salt of DMSO yields the spiro-epoxide, which is opened with... 

Phenyl thienyl ketone has been prepared by treatment of benzoyl chloride with thienylmercuric chloride 1 by treatment of thiophene with benzoyl chloride in the presence of thienylmercuric chloride,2 phosphorus pentoxide,3 stannic chloride,4 and aluminum chloride.5 It has also been prepared from thienyl-magnesium iodide and benzonitiile.6... 

Di-a-thienyl tellurium di-iodide, (C4H3S)2TeI2, is precipitated as a microcrystalline pow der v hen an ether solution of iodine is added dropwise to a solution of di-a-thienyl telluride in the same solvent. It crystallises from hot benzene as dark violet (permanganate coloured) hexagonal prisms, M.pt. 126 5° C., decomposing at 190° C. 

Di(3-benzo[6]thienyl)methane is obtained by treatment of 3-benzo-[6]thienylmagnesium bromide with 3-chloromethylbenzo [ thiophene.486 Two molecules of 3-benzo[6]thienylmagnesium iodide may be coupled by treatment with cupric chloride,305 but not with cupric bromide or nickel bromide,349 to yield 3,3 -di(benzo[6]thienyl). A claim349 to have prepared the same compound by the Ullmann reaction is probably not justified.305 The Ullmann reaction otherwise seems to be of general application in the benzo [6]thiophene series.87-483 Halobenzo[6]thiophenes76 105 511 can be selectively metallated in the 2-position by the use of w-butyllithium (Section VII). 

Methyl ketones can be prepared by the carbonylation of aryl, benzyl and thienyl bromides and iodides in the presence of tetramethyltin (equation 102). This reaction also requires raised temperature and pressure. [Ni(CO)2(PPh3)2] (101) was used as catalyst.473... 

Bromo-2-thienyl-thiophene-2-carbaldehyde (128), obtained from the photochemical coupling of 5-iodothiophene-2-carbaldehyde and 2-bro-mothiophene, can be reduced with NaBH4 129 was treated with propyne, copper iodide, and Pd(PPh3)4 under phase-transfer conditions to give a natural bithiophene 130 isolated from Arctium lappa (87JOC5243). 

An alternative to the use of the 2-thienyl group as a nontransferable ligand in h.o. cyanocuprates is the anion of DMSO (1) efficient alkylation of primary iodides at -78 °C... 

The 2-[3-(a-hydroxybenzyl)-2-thienyl]-3,4,4-trimethyl-2-oxazolinium iodide (335) reacted with phenylmagnesium bromide to give 4,6-diphenylthieno[2,3-c]furan (130) (85% yield) <89CBlll9>. 

Similar reactions starting with the ethylene acetals of 3-formyl- or 3-acetyl-2-thienyl dimethyl telluronium iodides yielded 3-formyl- or 3-acetyl-2-thienyl methyl tellurium. The acetals were hydrolyzed before the products were isolated2. 

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