Stirling in Dusseldorf

Stirling, James

doi:10.2307/4090917

Cited by 3 publications

(2 citation statements)

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“…However, different products are formed in these cases. In accordance with the classification of a base-induced ring opening of heterocycles previously made, 36b, our reaction follows the “ROI” (ring opening type I), which is extended to all eliminative ring openings of β-carbanions 36b. However, a more detailed study showed that the transformation of 7a to 17 occurs extremely fast or in a single step, with the cleavage of C(3)−I, C(2)−Te bonds and the triple bond formation occurring probably in a concerted process, since we have not been able to trap with electrophiles the hypothetical intermediate lithium derivative 15 in the same reaction, even at −105 °C.…”

Section: Resultssupporting

confidence: 70%

Iodocyclization of (Z)-1-(Butyltelluro)-1,4-diorganylbut-1-en-3-ynes. Synthesis and Reactions of 3-Iodotellurophenes

Dabdoub

Pereira

et al. 1996

J. Org. Chem.

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The iodocyclization of (Z)-tellurobutenynes 5a − g by reaction with I2/petroleum ether was studied in detail. 3-Iodotellurophenes 7a − f were formed, and optimum conditions to obtain these compounds in high yields were established. The reaction involves attack of iodide at the initially formed intermediate of type 10 followed by ring closure that is favored by the strong aromatic character of the resulting products. Two possible and alternative pathways for the ring closure are proposed to explain our observations: (a) transformation of 10 to 11 that undergoes further cyclization to give 7a − f (pathway a) or (b) direct cyclization of 10 to give tellurophene diiodide 9 (pathway b). The products and side products obtained are in agreement with the proposed mechanisms. Formation of 7a from ditelluride 14 and iodine provides additional evidence of the intermediacy of 11 (in pathway a). Structures of 7a and 5g were elucidated by X-ray crystallography. In the case of compound 5e, where a terminal triple bond was present, the resulting intermediate of type 10 also underwent the attack of iodide directly at the terminal carbon to give compound 12 together with 7e. Ring-opening of 3-iodotellurophene 7a occurs by reaction with n-butyllithium to form acyclic ditelluride 14 or monotelluride 16 depending on the alkyllithium amounts employed. Plausible mechanisms for these novel reactions are proposed and supported. Conversion of 7a to 3-(butyltelluro)-2,5-diphenyltellurophene (22) was carried out readily by an unusual “aromatic nucleophilic substitution” using the butyl tellurolate anion.

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Section: Resultssupporting

confidence: 70%

Iodocyclization of (Z)-1-(Butyltelluro)-1,4-diorganylbut-1-en-3-ynes. Synthesis and Reactions of 3-Iodotellurophenes

Dabdoub

Pereira

et al. 1996

J. Org. Chem.

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“…In Tanzania, for instance, medical care has been provided by personnel with less than full professional training for generations. There is extensive reliance on medical assistants, rural medical aids and village health aids, and more than 80 per centof the health care available is currently provided by such personnel (Stirling, 1976). The pattern is essentially similar in Uganda, Kenya and Zambia and also in Malawi, Botswana and Swaziland.…”

Section: Health Perspectives In Developing Commonwealth Countriesmentioning

confidence: 99%

Report of the Fifth Commonwealth Medical Conference

1978

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CMC (77) I/B2 C M C ( 7 7 ) I / B 3 CMC (77) II CMC(77)II/B1 CMC(77)II/B2 CMC (77) II/B3 CMC (77) II/B4 CMC (77) II/B5 CMC (77) II/B6 CMC(77)II/B7 CMC (77) II/B8 CMC(77)II/B9 CMC (77) II/B10 CMC(77)II/B11 CMC(77)II/B12 CMC(77)II/B13 CMC(77)II/B14 CMC(77)II/B15 CMC(77)II/B16 CMC(77)II/B17 CMC (77) III CMC (77) III/B1 CMC(77)III/B2 CMC (77) III/B3Review of British health aid to Commonwealth countries: 1974-76

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Oil spill in Hong Kong

Spooner

1977

Marine Pollution Bulletin

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Stirling in Dusseldorf

Cited by 3 publications

References 0 publications

Iodocyclization of (Z)-1-(Butyltelluro)-1,4-diorganylbut-1-en-3-ynes. Synthesis and Reactions of 3-Iodotellurophenes

Iodocyclization of (Z)-1-(Butyltelluro)-1,4-diorganylbut-1-en-3-ynes. Synthesis and Reactions of 3-Iodotellurophenes

Report of the Fifth Commonwealth Medical Conference

Oil spill in Hong Kong

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