Higher alkene acetylations, acetyl chloride

Cyclopropanation.1 The cyclopropanation of alkenes by this combination can be facilitated by sonication or by Ti(IV) chloride, but acetyl chloride is more effective. The effectiveness of this promotor may result from removal of traces of water and hydroxylic impurities. Yields using this expedient are generally higher (45-85%) than those obtained by the original Simmons-Smith conditions using diiodo-methane. 

The iron tricarbonyl unit has been described as a protecting group for a 1,3-diene, as in the acetylation of the complex of myrcene at low temperature (Scheme 20). The usual combinations of a,p- and p,"y-un-saturated ketones were formed. At higher temperatures, some acylation at the terminus of the diene complex was also observed. In an interesting extension, reaction of the complex with oxalyl chloride resulted in cyclization of the acid chloride initially formed by reaction at the alkene. ... 

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