methanol; ammonium chloride in not given mixt. stirring (-60°C, 3 h), decompn. with methanol, warming to 20°C, satd. NH4Cl soln. addn.; org. layer drying (MgSO4), fractionation; elem. anal.;

in hexane under Ar, soln. of N,N-diethylcrotonamide in hexane cooled to -60°C, soln. of Et3GeLi in hexane added dropwise, stirred for 3 h at -60°C, quenched with methanol; washed with satd. soln. of NH4Cl, dried (MgSO4), evapd., distd.; elem. anal.;