Scheme 4.

Optimized conditions for the addition of allylzinc bromide complexed with lithium chloride (7 a) to [1.1.1]propellane (1) followed by copper mediated acylation.

Optimized conditions for the addition of allylzinc bromide complexed with lithium chloride (7 a) to [1.1.1]propellane (1) followed by copper mediated acylation.