Alkenes alkoxy chlorination

However, a computational study124 shows that the Kishi model controls the stereoselectivity for (Z)-alkenes. Note also that in the Diels-Alder reactions of hexachloropentadiene with chiral alkenes, the inside alkoxy effect is attributed to electrostatic repulsion of the oxy group in the125 outside position with the chlorine atom of hexachloropentadiene in the 1-position. 

Bis(organooxy)diazirines are available by exchange of chlorine in 3-alkoxy-3-chloro-3//-diazirines for the alkoxy group. The diazirines thus formed decompose under mild conditions, at room temperature, to generate the bis(organooxy)carbenes which undergo addition to electrophilic alkenes to give cyclopropanes... 

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