ChemInform Abstract: An Easy Access to Homopropargylic Ethers.
Abstract
The chloromethyl ethers (III) [obtained from the alcohols (I), formaldehyde (II) and HCl] react regioselectively with allenyl aluminium reagents derived from propargyl bromides (IV) and aluminium, to give the homopropargyl ethers (Va)-(Vd).
ChemInform Abstract
The chloromethyl ethers (III) [obtained from the alcohols (I), formaldehyde (II) and HCl] react regioselectively with allenyl aluminium reagents derived from propargyl bromides (IV) and aluminium, to give the homopropargyl ethers (Va)-(Vd). The homopropargyl ethers (Ve) or the thioethers (IX) are obtained from the dioxolane (VI) or the thiophenol (VII) by the same procedure. This procedure is also used to obtain the protected synthon (Vf), required for the synthesis of an ecdysteroid analogue. Thus, (Vf) is obtained from (X) by the sequence shown in the scheme; the key step is the conversion of the alcohol (XIII) to the homopropargyl ether (Va).
