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RESEARCH PRODUCT
Addition von Phosphor‐Nucleophilen an Benzothiet
H.‐l. EckesHerbert MeierHans‐peter Niedermannsubject
chemistry.chemical_classificationAddition reactionChemistryStereochemistryAlcoholMedicinal chemistryAdductInorganic Chemistrychemistry.chemical_compoundSN1 reactionNucleophileIntramolecular forceYield (chemistry)Alkyldescription
Addition Reactions of Phosphorus Nucleophiles to Benzothiete Trialkyl phosphites 4 add to the o-quinoid form 2 of benzothiete (1) to yield the phosphonates 6. An intermolecular migration of an alkyl group from oxygen to sulfur is the most important feature of this transformation. The rearrangement – related to the Arbuzov reaction – can be avoided in a two-step process by the subsequent action of PCl3 and alcohol; thus the phosphonates 10 are generated. Analogous to 2 6, dimethyl phenylphosphinate (11) furnishes 13. In contrast, the cyclic esters 14a–d form 2:1 adducts, namely the 12- to 15-membered heterocyclic compounds 17a – d. An intramolecular rearrangement in a 1:1 adduct is only observed for the 1,3,2-dioxaphosphepine 14e, a benzylic system which allows an SN1 process generating the 1,6,2-oxathiaphosphecine 18e. A similar rearrangement at a tertiary carbon center is prevented by the competitive addition of water (1 + 14f 20).
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1991-02-01 | Chemische Berichte |