Trans- — chloride

Figure 4 Hydrolysis scheme for cisplatin-based anticancer agents. Where L = U = NH3 cisplatin is indicated. When L = NH3 and V = 2-picoline or cha the rates of aquation of the trans-chloride ligands are different.

The Os=N group has a strong trans-influence, reflected in both the labiliza-tion of the trans-chloride (a similar reaction occurs with OsbJBrs") and in the pronounced lengthening of the trans-Os—Cl bond (2.605 A versus 2.362 A). 

Reactions of the corresponding tosylates with Me3SnLi proceeded in low yield, but products of inverted configuration were produced. The cis and trans chlorides led to extensive loss of configuration at carbon with a slight preference for inversion. 

Reactions of the isomeric 5-methyl-3-chlorocyclohexenes with MesGeLi (Scheme 22) were complicated by the formation of by-products resulting from double bond migration 58 and disproportionation 59 and 6049. These side reactions could be minimized by careful control of conditions. The predominant process was found to be Sat2 displacement for both isomers, with the trans chloride showing somewhat higher specificity than the cis isomer. 

The trichloroammine can have either a cw-chloride replaced by water to give the cw-aquo complex, or it can have the trans-chloride replaced, and then each of these two isomers in turn can hydrolyze further. They will each lead to a common cw-diaquo species, and the cw-dichloroaquoammineplatinum(II) will also lead to a possible /raws-diaquo isomer. 

The action of an equivalent amount of the alkyl sulfide on potassium tetrachloroplatinate(II) yields the bright yellow trans chloride, while excess sulfide gives the very weakly greenish-yellow cis chloride.112,6,7 Since separation of the two isomers is a difficult and lengthy process, experimental conditions should be chosen so that only one isomer is formed. This is done, as far as possible, in the methods given below for the diethyl sulfide compounds. 

IrCl3N,C4H HCl 2H2O, Iridium(ni), dichlorobis( 1,2-ethanediamine)-, trans-, chloride, monohydrochloride, dihy-diate, 24 287... 

PtClNPSejCagHzs, Platinum(II), chloro-(iV,N-diethyldiselenocarbamato)(tri-phenylphosphine)-, 21 10 PtCl2HgIN2Pt, Platinum(II), diamminechlo-roiodo-, trans-, chloride, 22 124... 

Stork [11], as well as Corey [12], have shown that methallylmagnesium chloride couples with allylic chlorides affording a mixture of 8, 2 and Sn2 products. However, Stork [11] has found that the use of hexamethylphosphoramide (HMPA) as a cosolvent allows the formation of the sole 8, 2 product 10, without any rearrangement of the double bond, after reaction with either cis- or trans-chlorides 9 [Eq. (4)]. 

C. The characteristic infrared stretch of the ReN triple bond has not been found due to interference from Ph modes the ReCl stretch occurs at 323 cm (Nujol mull). Despite the color of the complex in the solid state and the yellow color of a CH2CI2 solution, no distinctive features appear in the visible region of the spectrum. The dipole moment of 1.6 (3) D is consistent with the X-ray crystal structure obtained elsewhere that reveals a distorted square pyramid with an apical nitrido ligand and mutually trans chloride ligands in the basal plane. The triphenylphosphine ligands are distorted toward the empty rhenium coordination site. 

RUCI3N4C (,H24 2H2O, Ruthenium(III), dichloro(l,4,8,ll-tetraazacyclotetra-decane)-, trans-, chloride, dihydrate, 29 166... 

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