Preparation of phosphorothioate oligomers

An azaphospholane of Formula VIb:

• 115
• wherein:
• y is X or W wherein X is halogen, dialkylamino, imidazole, triazole or substituted phenoxy wherein said substituents are electron withdrawing, and W has the formula:
• 116
• wherein:
• Q is independently O or S;
• R1 is a hydroxyl Protecting group;
• R2 is a chiral auxiliary of formula —C(R8)R3—C(R16)R5—CHR6—NHR7;
• R3 is hydrogen, alkyl, cyanomethyl, monohalomethyl, dihalomethyl, trihalomethyl, —CH2Si(R4)3, or —CH2—SOkR4 where k is 0, 1 or 2;
• R4 is independently alkyl, aryl, aralkyl or alkaryl having up to 15 carbon atoms;
• R5 is H, —CN, —Si(R4)3, SOkR4 or halogen;
• or R8 and R16 are each H, and R3 and R5, together, form one of the structures
• 117
• wherein:
• R10 and R11 are H, alkyl having from 1 to about 10 carbons, —CH2C(═O)OR22, —CH2CN, —CH2Si(CH3)3, or o- or p-C6H4—R21;
• R21 is hydrogen, —O—C(═O)CH3, alkoxy having from 1 to about 10 carbons, —NO2, or —N(R22)2;
• R22 is independently H or alkyl having from one to about 10 carbon atoms;
• p is 1 or 2;
• Z1 and Z2 are independently halogen, CN, —Si(CH3)3, and —C(═O)OR22;
• R30 is hydrogen, —O—C(═O)CH3, alkoxy having from 1 to about 10 carbons, or —O—Si(R4)3;
• R6 is H, alkyl or aralkyl having up to 15 carbon atoms;
• or R5 and R6, together with the atoms to which they are attached, form a 5 or 6 membered ring;
• R7 is alkyl or aralkyl having up to 15 carbon atoms;
• or R6 and R7, together, form one of the structures
• 118
• wherein X, T, and Z are independently CH or NH;
• or Z and R5, together with the atoms to which they are attached, form a phenyl ring;
• R8 is H or methyl;
• R9 is a hydroxyl protecting group or a solid support;
• R16 is H, alkyl or aralkyl having up to 15 carbon atoms;
• B is a nucleobase;
• and
• n is an integer from 0 to 50.

An oligomeric compound comprising a moiety having a phosphite linkage of the Formula XXX:

• 125
• wherein:
• R3 is hydrogen, alkyl, cyanomethyl, monohalomethyl, dihalomethyl, trihalomethyl, —CH2Si(R4)3, or —CH2—SOkR4 where k is 0, 1 or 2;
• R4 is independently alkyl, aryl, aralkyl or alkaryl having up to 15 carbon atoms;
• R5 is H, —CN, —Si(R4)3, SOkR4 or halogen;
• or R8 and R16 are each H, and R3 and R3, together, form one of the structures
• 126
• wherein:
• R10 and R11 are H, alkyl having from 1 to about 10 carbons, —CH2C(═O)OR22, —CH2CN, —CH2Si(CH3)3, or o- or p-C6H4—R21;
• R21 is hydrogen, —O—C(═O)CH3, alkoxy having from 1 to about 10 carbons, —NO2, or —N(R22)2;
• R22 is independently H or alkyl having from one to about 10 carbon atoms;
• p is 1 or 2;
• Z1 and Z2 are independently halogen, CN, —Si(CH3)3, and —C(═O)OR22;
• R30 is hydrogen, —O—C(═O)CH3, alkoxy having from 1 to about 10 carbons, or —O—Si(R4)3;
• R6 is H, alkyl or aralkyl having up to 15 carbon atoms;
• or R5 and R6, together with the atoms to which they are attached, form a 5 or 6 membered ring;
• R′ is alkyl or aralkyl having up to 15 carbon atoms;
• or R6 and R7, together, form one of the structures
• 127
• wherein X, T, and Z are independently CH or NH;
• or Z and R5, together with the atoms to which they are attached, form a phenyl ring;
• R8 is H or methyl;
• R9 is a hydroxyl protecting group or a solid support;
• R16 is H, alkyl or aralkyl having up to 15 carbon atoms;
• B is a nucleobase;
• and
• n is an integer from 0 to 50.