Altho~~gh fluoroacyl derivatives of transition metals have been l;no\\:n for seine time, little work has been done on the analogous derivatives of other metals and metalloids (1). Therefore, since compounds wit11 Si1-Sn and -4s-As bonds are readily cleaved by fluoroalkyl iodides to give fluoroalkyl derivatives of tin or arsenic (2-4), ... The last reaction inay proceed through initial formation of the trifluoroacetyl compound follo\\.ed by decarbonylation. (CI-I~)?.ASC(O)CI; ...