Substitution of Secondary Propargylic Phosphates Using Aryl-Lithium-Based Copper Reagents

نویسندگان

چکیده

The substitution of secondary propargylic phosphates ROP(O)(OEt)2 where R = [Ph(CH2)2]C(H)(C≡CTMS)] Ph(CH2)2CH(OP(O)(OEt)2)(C≡CTMS) with copper reagents derived from PhLi and salts such as CuCl, CuCN, Cu(acac)2 was studied to establish an ArLi-based reagent system. Among the prepared, PhLi/CuCl (2:1) showed 98% α regioselectivity (rs), while PhLi/Cu(acac)2 γ selective (>99% rs). prepared in situ PhI PhBr by Li-halogen exchange t-BuLi also used for substitution. A study using (S)-phosphate disclosed 99% enantiospecificity (es) inversion stereochemistry. five substituted aryl produced corresponding products high rs es values. Similar reactivity selectivity were observed 2-furyl 2-thienyl reagents, which via direct lithiation n-BuLi.

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ژورنال

عنوان ژورنال: Catalysts

سال: 2023

ISSN: ['2073-4344']

DOI: https://doi.org/10.3390/catal13071084